add support for negative filters (-F field!=regex)

Bumps [github.com/hashicorp/hcl/v2](https://github.com/hashicorp/hcl) from 2.22.0 to 2.23.0.
- [Release notes](https://github.com/hashicorp/hcl/releases)
- [Changelog](https://github.com/hashicorp/hcl/blob/main/CHANGELOG.md)
- [Commits](https://github.com/hashicorp/hcl/compare/v2.22.0...v2.23.0)

---
updated-dependencies:
- dependency-name: github.com/hashicorp/hcl/v2
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/ISSUE_TEMPLATE/bug_report.md

@@ -7,7 +7,7 @@ assignees: TLINDEN
 
 ---
 
-**Describtion**
+**Description**
 <!-- Please provide a clear and concise description of the issue: -->
 
 

.github/ISSUE_TEMPLATE/feature_request.md

@@ -7,7 +7,7 @@ assignees: TLINDEN
 
 ---
 
-**Describtion**
+**Description**
 <!-- Please provide a clear and concise description of the feature you desire: -->
 
 

.github/dependabot.yml

@@ -0,0 +1,10 @@
+version: 2
+updates:
+  - package-ecosystem: "gomod"
+    directory: "/"
+    schedule:
+      interval: "monthly"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+        interval: "monthly"

.github/workflows/ci.yaml

@@ -4,19 +4,21 @@ jobs:
   build:
     strategy:
       matrix:
-        version: [1.18, 1.19]
-        os: [ubuntu-latest, windows-latest, macos-latest]
+        version: ['1.22']
+        # windows-latest removed, see:
+        # https://github.com/rogpeppe/go-internal/issues/284
+        os: [ubuntu-latest, macos-latest]
     name: Build
     runs-on: ${{ matrix.os }}
     steps:
-    - name: Set up Go 1.18
-      uses: actions/setup-go@v3
+    - name: Set up Go ${{ matrix.version }}
+      uses: actions/setup-go@v5
       with:
-        go-version: ${{ matrix.version }}
+        go-version: '${{ matrix.version }}'
       id: go
 
     - name: checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: build
       run: make
@@ -28,11 +30,11 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/setup-go@v3
+      - uses: actions/setup-go@v5
         with:
-          go-version: 1.18
-      - uses: actions/checkout@v3
+          go-version: 1.22
+      - uses: actions/checkout@v4
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v6
         with:
           skip-cache: true

.github/workflows/release.yaml

@@ -0,0 +1,32 @@
+name: build-and-test
+on:
+  push:
+    tags:
+      - "*"
+
+jobs:
+  release:
+    name: Build Release Assets
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Set up Go
+        uses: actions/setup-go@v1
+        with:
+          go-version: 1.22.11
+
+      - name: Build the executables
+        run: ./mkrel.sh tablizer ${{ github.ref_name}}
+
+      - name: List the executables
+        run: ls -l ./releases
+
+      - name: Upload the binaries
+        uses: svenstaro/upload-release-action@v2
+        with:
+          repo_token: ${{ secrets.GITHUB_TOKEN }}
+          tag: ${{ github.ref_name }}
+          file: ./releases/*
+          file_glob: true

.gitignore

@@ -1,2 +1,3 @@
 releases
 tablizer
+*.out

Makefile

@@ -53,8 +53,7 @@ buildlocal:
 	go build -ldflags "-X 'github.com/tlinden/tablizer/cfg.VERSION=$(VERSION)'"
 
 release:
-	./mkrel.sh $(tool) $(version)
-	gh release create $(version) --generate-notes releases/*
+	gh release create $(version) --generate-notes
 
 install: buildlocal
 	install -d -o $(UID) -g $(GID) $(PREFIX)/bin
@@ -66,11 +65,10 @@ clean:
 	rm -rf $(tool) releases coverage.out
 
 test:
-	go test -v ./...
-	bash t/test.sh
+	go test ./... $(OPTS)
 
 singletest:
-	@echo "Call like this: ''make singletest TEST=TestPrepareColumns MOD=lib"
+	@echo "Call like this: 'make singletest TEST=TestPrepareColumns MOD=lib'"
 	go test -run $(TEST) github.com/tlinden/tablizer/$(MOD)
 
 cover-report:
@@ -91,3 +89,11 @@ show-versions: buildlocal
 
 goupdate:
 	go get -t -u=patch ./...
+
+lint:
+	golangci-lint run
+
+# keep til ireturn
+lint-full:
+	golangci-lint run --enable-all --exclude-use-default --disable exhaustivestruct,exhaustruct,depguard,interfacer,deadcode,golint,structcheck,scopelint,varcheck,ifshort,maligned,nosnakecase,godot,funlen,gofumpt,cyclop,noctx,gochecknoglobals,paralleltest,forbidigo,gci,godox,goimports,ireturn,stylecheck,testpackage,mirror,nestif,revive,goerr113,gomnd
+	gocritic check -enableAll *.go

README.md

@@ -8,6 +8,49 @@ Tablizer  can   be  used   to  re-format   tabular  output   of  other
 programs. While you  could do this using standard unix  tools, in some
 cases it's a hard job.
 
+Usage:
+```default
+Usage:
+  tablizer [regex] [file, ...] [flags]
+
+Operational Flags:
+  -c, --columns string              Only show the speficied columns (separated by ,)
+  -v, --invert-match                select non-matching rows
+  -n, --no-numbering                Disable header numbering
+  -N, --no-color                    Disable pattern highlighting
+  -H, --no-headers                  Disable headers display
+  -s, --separator string            Custom field separator
+  -k, --sort-by int                 Sort by column (default: 1)
+  -z, --fuzzy                       Use fuzzy search [experimental]
+  -F, --filter field[!]=reg         Filter given field with regex, can be used multiple times
+  -T, --transpose-columns string    Transpose the speficied columns (separated by ,)
+  -R, --regex-transposer /from/to/  Apply /search/replace/ regexp to fields given in -T
+
+Output Flags (mutually exclusive):
+  -X, --extended                    Enable extended output
+  -M, --markdown                    Enable markdown table output
+  -O, --orgtbl                      Enable org-mode table output
+  -S, --shell                       Enable shell evaluable output
+  -Y, --yaml                        Enable yaml output
+  -C, --csv                         Enable CSV output
+  -A, --ascii                       Default output mode, ascii tabular
+  -L, --hightlight-lines            Use alternating background colors for tables
+
+Sort Mode Flags (mutually exclusive):
+  -a, --sort-age                    sort according to age (duration) string
+  -D, --sort-desc                   Sort in descending order (default: ascending)
+  -i, --sort-numeric                sort according to string numerical value
+  -t, --sort-time                   sort according to time string
+
+Other Flags:
+      --completion <shell>         Generate the autocompletion script for <shell>
+  -f, --config <file>              Configuration file (default: ~/.config/tablizer/config)
+  -d, --debug                      Enable debugging
+  -h, --help                       help for tablizer
+  -m, --man                        Display manual page
+  -V, --version                    Print program version
+```
+
 Let's take this output:
 ```
 % kubectl get pods -o wide
@@ -70,8 +113,36 @@ NAME(1)                      READY(2) STATUS(3)  RESTARTS(4)    AGE(5)
 repldepl-7bcd8d5b64-q2bf4    1/1      Running    1 (69m ago)    5h26m
 ```
 
+Sometimes a filter regex is to broad  and you wish to filter only on a
+particular column. This is possible using `-F`:
+```
+% kubectl get pods | tablizer -n -Fname=2
+NAME                            READY   STATUS  RESTARTS        AGE
+repldepl-7bcd8d5b64-q2bf4       1/1     Running 1 (69m ago)     5h26m
+```
+
+Here we filtered  the `NAME` column for `2`, which  would have matched
+otherwise on all rows.
+
 There are more output modes like org-mode (orgtbl) and markdown.
 
+You can also use it to modify certain cells using regular expression
+matching. For example:
+
+```shell
+kubectl get pods | tablizer -n -T4 -R '/ /-/'
+NAME                            READY   STATUS  RESTARTS        AGE
+repldepl-7bcd8d5b64-7zq4l       1/1     Running 1-(69m-ago)     5h26m
+repldepl-7bcd8d5b64-m48n8       1/1     Running 1-(69m-ago)     5h26m
+repldepl-7bcd8d5b64-q2bf4       1/1     Running 1-(69m-ago)     5h26m
+```
+
+Here, we modified the 4th column (`-T4`) by replacing every space with
+a dash. If you need to work with `/` characters, you can also use any
+other separator, for instance: `-R '| |-|'`.
+
+
+
 ## Demo
 
 [![asciicast](demo/tablizer-demo.gif)](https://asciinema.org/a/9FKc3HPnlg8D2X8otheleEa9t)
@@ -127,6 +198,41 @@ In order to report a bug, unexpected behavior, feature requests
 or to submit a patch, please open an issue on github:
 https://github.com/TLINDEN/tablizer/issues.
 
+## Prior Art
+
+When I started with tablizer I was not aware that other tools
+exist. Here is a non-exhausive list of the ones I find especially
+awesome:
+
+### [miller](https://github.com/johnkerl/miller)
+
+This is a really powerful tool to work with tabular data and it also
+allows other inputs as json, csv etc. You can filter, manipulate,
+create pipelines, there's even a programming language builtin to do
+even more amazing things.
+
+### [csvq](https://github.com/mithrandie/csvq)
+
+Csvq allows you to query CSV and TSV data using SQL queries. How nice
+is that? Highly recommended if you have to work with a large (and
+wide) dataset and need to apply a complicated set of rules.
+
+### [goawk](https://github.com/benhoyt/goawk)
+
+Goawk is a 100% POSIX compliant AWK implementation in GO, which also
+supports CSV and TSV data as input (using `-i csv` for example). You
+can apply any kind of awk code to your tabular data, there are no
+limit to your creativity!
+
+### [teip](https://github.com/greymd/teip)
+
+I particularly like teip, it's a real gem. You can use it to drill
+"holes" into your tabular data and modify these "holes" using small
+external unix commands such as grep or sed. The possibilities are
+endless, you can even use teip to modify data inside a hole created by
+teip. Highly recommended.
+
+
 ## Copyright and license
 
 This software is licensed under the GNU GENERAL PUBLIC LICENSE version 3.

TODO.md

@@ -6,13 +6,3 @@
 
 - add --no-headers option
 
-### Lisp Plugin Infrastructure using zygo
-
-Hooks:
-
-| Filter    | Purpose                                                     | Args                | Return |
-|-----------|-------------------------------------------------------------|---------------------|--------|
-| filter    | include or exclude lines                                    | row as hash         | bool   |
-| process   | do calculations with data, store results in global lisp env | whole dataset       | nil    |
-| transpose | modify a cell                                               | headername and cell | cell   |
-| append    | add one or more rows to the dataset (use this to add stats) | nil                 | rows   |

cfg/config.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2022 Thomas von Dein
+Copyright © 2022-2025 Thomas von Dein
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -19,25 +19,24 @@ package cfg
 import (
 	"errors"
 	"fmt"
-	"log"
 	"os"
 	"regexp"
+	"strings"
 
-	"github.com/glycerine/zygomys/zygo"
 	"github.com/gookit/color"
 	"github.com/hashicorp/hcl/v2/hclsimple"
 )
 
 const DefaultSeparator string = `(\s\s+|\t)`
-const Version string = "v1.1.0"
+const Version string = "v1.3.1"
+const MAXPARTS = 2
 
-var DefaultLoadPath string = os.Getenv("HOME") + "/.config/tablizer/lisp"
-var DefaultConfigfile string = os.Getenv("HOME") + "/.config/tablizer/config"
+var DefaultConfigfile = os.Getenv("HOME") + "/.config/tablizer/config"
 
 var VERSION string // maintained by -x
 
 // public config, set via config file or using defaults
-type Configuration struct {
+type Settings struct {
 	FG             string `hcl:"FG"`
 	BG             string `hcl:"BG"`
 	HighlightFG    string `hcl:"HighlightFG"`
@@ -48,6 +47,22 @@ type Configuration struct {
 	HighlightHdrBG string `hcl:"HighlightHdrBG"`
 }
 
+type Transposer struct {
+	Search  regexp.Regexp
+	Replace string
+}
+
+type Pattern struct {
+	Pattern   string
+	PatternRe *regexp.Regexp
+	Negate    bool
+}
+
+type Filter struct {
+	Regex  *regexp.Regexp
+	Negate bool
+}
+
 // internal config
 type Config struct {
 	Debug          bool
@@ -58,14 +73,19 @@ type Config struct {
 	Separator      string
 	OutputMode     int
 	InvertMatch    bool
-	Pattern        string
-	PatternR       *regexp.Regexp
+	Patterns       []*Pattern
 	UseFuzzySearch bool
 	UseHighlight   bool
 
-	SortMode       string
-	SortDescending bool
-	SortByColumn   int
+	SortMode        string
+	SortDescending  bool
+	SortByColumn    string // 1,2
+	UseSortByColumn []int  // []int{1,2}
+
+	TransposeColumns    string       // 1,2
+	UseTransposeColumns []int        // []int{1,2}
+	Transposers         []string     // []string{"/ /-/", "/foo/bar/"}
+	UseTransposers      []Transposer // {Search: re, Replace: string}
 
 	/*
 	 FIXME: make configurable somehow, config file or ENV
@@ -78,17 +98,17 @@ type Config struct {
 
 	NoColor bool
 
-	// special  case: we use the  config struct to transport  the lisp
-	// env trough the program
-	Lisp *zygo.Zlisp
-
-	// a path containing lisp scripts to be loaded on startup
-	LispLoadPath string
-
 	// config file, optional
 	Configfile string
 
-	Configuration Configuration
+	Settings Settings
+
+	// used for field filtering
+	Rawfilters []string
+	Filters    map[string]Filter //map[string]*regexp.Regexp
+
+	// -r <file>
+	InputFile string
 }
 
 // maps outputmode short flags to output mode, ie. -O => -o orgtbl
@@ -110,7 +130,7 @@ const (
 	Shell
 	Yaml
 	CSV
-	Ascii
+	ASCII
 )
 
 // various sort types
@@ -120,11 +140,8 @@ type Sortmode struct {
 	Age     bool
 }
 
-// valid lisp hooks
-var ValidHooks []string
-
 // default color schemes
-func (c *Config) Colors() map[color.Level]map[string]color.Color {
+func (conf *Config) Colors() map[color.Level]map[string]color.Color {
 	colors := map[color.Level]map[string]color.Color{
 		color.Level16: {
 			"bg": color.BgGreen, "fg": color.FgWhite,
@@ -142,89 +159,86 @@ func (c *Config) Colors() map[color.Level]map[string]color.Color {
 		},
 	}
 
-	if len(c.Configuration.BG) > 0 {
-		colors[color.Level16]["bg"] = ColorStringToBGColor(c.Configuration.BG)
-		colors[color.Level256]["bg"] = ColorStringToBGColor(c.Configuration.BG)
-		colors[color.LevelRgb]["bg"] = ColorStringToBGColor(c.Configuration.BG)
+	if len(conf.Settings.BG) > 0 {
+		colors[color.Level16]["bg"] = ColorStringToBGColor(conf.Settings.BG)
+		colors[color.Level256]["bg"] = ColorStringToBGColor(conf.Settings.BG)
+		colors[color.LevelRgb]["bg"] = ColorStringToBGColor(conf.Settings.BG)
 	}
 
-	if len(c.Configuration.FG) > 0 {
-		colors[color.Level16]["fg"] = ColorStringToColor(c.Configuration.FG)
-		colors[color.Level256]["fg"] = ColorStringToColor(c.Configuration.FG)
-		colors[color.LevelRgb]["fg"] = ColorStringToColor(c.Configuration.FG)
+	if len(conf.Settings.FG) > 0 {
+		colors[color.Level16]["fg"] = ColorStringToColor(conf.Settings.FG)
+		colors[color.Level256]["fg"] = ColorStringToColor(conf.Settings.FG)
+		colors[color.LevelRgb]["fg"] = ColorStringToColor(conf.Settings.FG)
 	}
 
-	if len(c.Configuration.HighlightBG) > 0 {
-		colors[color.Level16]["hlbg"] = ColorStringToBGColor(c.Configuration.HighlightBG)
-		colors[color.Level256]["hlbg"] = ColorStringToBGColor(c.Configuration.HighlightBG)
-		colors[color.LevelRgb]["hlbg"] = ColorStringToBGColor(c.Configuration.HighlightBG)
+	if len(conf.Settings.HighlightBG) > 0 {
+		colors[color.Level16]["hlbg"] = ColorStringToBGColor(conf.Settings.HighlightBG)
+		colors[color.Level256]["hlbg"] = ColorStringToBGColor(conf.Settings.HighlightBG)
+		colors[color.LevelRgb]["hlbg"] = ColorStringToBGColor(conf.Settings.HighlightBG)
 	}
 
-	if len(c.Configuration.HighlightFG) > 0 {
-		colors[color.Level16]["hlfg"] = ColorStringToColor(c.Configuration.HighlightFG)
-		colors[color.Level256]["hlfg"] = ColorStringToColor(c.Configuration.HighlightFG)
-		colors[color.LevelRgb]["hlfg"] = ColorStringToColor(c.Configuration.HighlightFG)
+	if len(conf.Settings.HighlightFG) > 0 {
+		colors[color.Level16]["hlfg"] = ColorStringToColor(conf.Settings.HighlightFG)
+		colors[color.Level256]["hlfg"] = ColorStringToColor(conf.Settings.HighlightFG)
+		colors[color.LevelRgb]["hlfg"] = ColorStringToColor(conf.Settings.HighlightFG)
 	}
 
-	if len(c.Configuration.NoHighlightBG) > 0 {
-		colors[color.Level16]["nohlbg"] = ColorStringToBGColor(c.Configuration.NoHighlightBG)
-		colors[color.Level256]["nohlbg"] = ColorStringToBGColor(c.Configuration.NoHighlightBG)
-		colors[color.LevelRgb]["nohlbg"] = ColorStringToBGColor(c.Configuration.NoHighlightBG)
+	if len(conf.Settings.NoHighlightBG) > 0 {
+		colors[color.Level16]["nohlbg"] = ColorStringToBGColor(conf.Settings.NoHighlightBG)
+		colors[color.Level256]["nohlbg"] = ColorStringToBGColor(conf.Settings.NoHighlightBG)
+		colors[color.LevelRgb]["nohlbg"] = ColorStringToBGColor(conf.Settings.NoHighlightBG)
 	}
 
-	if len(c.Configuration.NoHighlightFG) > 0 {
-		colors[color.Level16]["nohlfg"] = ColorStringToColor(c.Configuration.NoHighlightFG)
-		colors[color.Level256]["nohlfg"] = ColorStringToColor(c.Configuration.NoHighlightFG)
-		colors[color.LevelRgb]["nohlfg"] = ColorStringToColor(c.Configuration.NoHighlightFG)
+	if len(conf.Settings.NoHighlightFG) > 0 {
+		colors[color.Level16]["nohlfg"] = ColorStringToColor(conf.Settings.NoHighlightFG)
+		colors[color.Level256]["nohlfg"] = ColorStringToColor(conf.Settings.NoHighlightFG)
+		colors[color.LevelRgb]["nohlfg"] = ColorStringToColor(conf.Settings.NoHighlightFG)
 	}
 
-	if len(c.Configuration.HighlightHdrBG) > 0 {
-		colors[color.Level16]["hdrbg"] = ColorStringToBGColor(c.Configuration.HighlightHdrBG)
-		colors[color.Level256]["hdrbg"] = ColorStringToBGColor(c.Configuration.HighlightHdrBG)
-		colors[color.LevelRgb]["hdrbg"] = ColorStringToBGColor(c.Configuration.HighlightHdrBG)
+	if len(conf.Settings.HighlightHdrBG) > 0 {
+		colors[color.Level16]["hdrbg"] = ColorStringToBGColor(conf.Settings.HighlightHdrBG)
+		colors[color.Level256]["hdrbg"] = ColorStringToBGColor(conf.Settings.HighlightHdrBG)
+		colors[color.LevelRgb]["hdrbg"] = ColorStringToBGColor(conf.Settings.HighlightHdrBG)
 	}
 
-	if len(c.Configuration.HighlightHdrFG) > 0 {
-		colors[color.Level16]["hdrfg"] = ColorStringToColor(c.Configuration.HighlightHdrFG)
-		colors[color.Level256]["hdrfg"] = ColorStringToColor(c.Configuration.HighlightHdrFG)
-		colors[color.LevelRgb]["hdrfg"] = ColorStringToColor(c.Configuration.HighlightHdrFG)
+	if len(conf.Settings.HighlightHdrFG) > 0 {
+		colors[color.Level16]["hdrfg"] = ColorStringToColor(conf.Settings.HighlightHdrFG)
+		colors[color.Level256]["hdrfg"] = ColorStringToColor(conf.Settings.HighlightHdrFG)
+		colors[color.LevelRgb]["hdrfg"] = ColorStringToColor(conf.Settings.HighlightHdrFG)
 	}
 
 	return colors
 }
 
 // find supported color mode, modifies config based on constants
-func (c *Config) DetermineColormode() {
+func (conf *Config) DetermineColormode() {
 	if !isTerminal(os.Stdout) {
 		color.Disable()
 	} else {
 		level := color.TermColorLevel()
-		colors := c.Colors()
+		colors := conf.Colors()
 
-		c.ColorStyle = color.New(colors[level]["bg"], colors[level]["fg"])
-		c.HighlightStyle = color.New(colors[level]["hlbg"], colors[level]["hlfg"])
-		c.NoHighlightStyle = color.New(colors[level]["nohlbg"], colors[level]["nohlfg"])
-		c.HighlightHdrStyle = color.New(colors[level]["hdrbg"], colors[level]["hdrfg"])
+		conf.ColorStyle = color.New(colors[level]["bg"], colors[level]["fg"])
+		conf.HighlightStyle = color.New(colors[level]["hlbg"], colors[level]["hlfg"])
+		conf.NoHighlightStyle = color.New(colors[level]["nohlbg"], colors[level]["nohlfg"])
+		conf.HighlightHdrStyle = color.New(colors[level]["hdrbg"], colors[level]["hdrfg"])
 	}
 }
 
 // Return true if current terminal is interactive
 func isTerminal(f *os.File) bool {
 	o, _ := f.Stat()
-	if (o.Mode() & os.ModeCharDevice) == os.ModeCharDevice {
-		return true
-	} else {
-		return false
-	}
+
+	return (o.Mode() & os.ModeCharDevice) == os.ModeCharDevice
 }
 
+// main program version
+// generated  version string, used  by -v contains  lib.Version on
+//
+//	main branch, and lib.Version-$branch-$lastcommit-$date on
+//
+// development branch
 func Getversion() string {
-	// main program version
-
-	// generated  version string, used  by -v contains  lib.Version on
-	//  main  branch,   and  lib.Version-$branch-$lastcommit-$date  on
-	// development branch
-
 	return fmt.Sprintf("This is tablizer version %s", VERSION)
 }
 
@@ -256,66 +270,155 @@ func (conf *Config) PrepareModeFlags(flag Modeflag) {
 	case flag.C:
 		conf.OutputMode = CSV
 	default:
-		conf.OutputMode = Ascii
+		conf.OutputMode = ASCII
 	}
 }
 
-func (c *Config) CheckEnv() {
-	// check for environment vars, command line flags have precedence,
-	// NO_COLOR is being checked by the color module itself.
-	if !c.NoNumbering {
-		_, set := os.LookupEnv("T_NO_HEADER_NUMBERING")
-		if set {
-			c.NoNumbering = true
+func (conf *Config) PrepareFilters() error {
+	conf.Filters = make(map[string]Filter, len(conf.Rawfilters))
+
+	for _, rawfilter := range conf.Rawfilters {
+		filter := Filter{}
+
+		parts := strings.Split(rawfilter, "!=")
+		if len(parts) != MAXPARTS {
+			parts = strings.Split(rawfilter, "=")
+
+			if len(parts) != MAXPARTS {
+				return errors.New("filter field and value must be separated by '=' or '!='")
+			}
+		} else {
+			filter.Negate = true
 		}
-	}
 
-	if len(c.Columns) == 0 {
-		cols := os.Getenv("T_COLUMNS")
-		if len(cols) > 1 {
-			c.Columns = cols
+		reg, err := regexp.Compile(parts[1])
+		if err != nil {
+			return fmt.Errorf("failed to compile filter regex for field %s: %w",
+				parts[0], err)
 		}
+
+		filter.Regex = reg
+		conf.Filters[strings.ToLower(parts[0])] = filter
 	}
-}
-
-func (c *Config) ApplyDefaults() {
-	// mode specific defaults
-	if c.OutputMode == Yaml || c.OutputMode == CSV {
-		c.NoNumbering = true
-	}
-
-	ValidHooks = []string{"filter", "process", "transpose", "append"}
-}
-
-func (c *Config) PreparePattern(pattern string) error {
-	PatternR, err := regexp.Compile(pattern)
-
-	if err != nil {
-		return errors.Unwrap(fmt.Errorf("Regexp pattern %s is invalid: %w", c.Pattern, err))
-	}
-
-	c.PatternR = PatternR
-	c.Pattern = pattern
 
 	return nil
 }
 
-func (c *Config) ParseConfigfile() error {
-	if path, err := os.Stat(c.Configfile); !os.IsNotExist(err) {
-		if !path.IsDir() {
-			configstring, err := os.ReadFile(path.Name())
-			if err != nil {
-				return err
-			}
+// check if transposers match transposer columns and prepare transposer structs
+func (conf *Config) PrepareTransposers() error {
+	if len(conf.Transposers) != len(conf.UseTransposeColumns) {
+		return fmt.Errorf("the number of transposers needs to correspond to the number of transpose columns: %d != %d",
+			len(conf.Transposers), len(conf.UseTransposeColumns))
+	}
 
-			err = hclsimple.Decode(
-				path.Name(), []byte(configstring),
-				nil, &c.Configuration,
-			)
-			if err != nil {
-				log.Fatalf("Failed to load configuration: %s", err)
+	for _, transposer := range conf.Transposers {
+		parts := strings.Split(transposer, string(transposer[0]))
+		if len(parts) != 4 {
+			return fmt.Errorf("transposer function must have the format /regexp/replace-string/")
+		}
+
+		conf.UseTransposers = append(conf.UseTransposers,
+			Transposer{
+				Search:  *regexp.MustCompile(parts[1]),
+				Replace: parts[2]},
+		)
+	}
+
+	return nil
+}
+
+func (conf *Config) CheckEnv() {
+	// check for environment vars, command line flags have precedence,
+	// NO_COLOR is being checked by the color module itself.
+	if !conf.NoNumbering {
+		_, set := os.LookupEnv("T_NO_HEADER_NUMBERING")
+		if set {
+			conf.NoNumbering = true
+		}
+	}
+
+	if len(conf.Columns) == 0 {
+		cols := os.Getenv("T_COLUMNS")
+		if len(cols) > 1 {
+			conf.Columns = cols
+		}
+	}
+}
+
+func (conf *Config) ApplyDefaults() {
+	// mode specific defaults
+	if conf.OutputMode == Yaml || conf.OutputMode == CSV {
+		conf.NoNumbering = true
+	}
+}
+
+func (conf *Config) PreparePattern(patterns []*Pattern) error {
+	// regex checks if a pattern looks like /$pattern/[i!]
+	flagre := regexp.MustCompile(`^/(.*)/([i!]*)$`)
+
+	for _, pattern := range patterns {
+		matches := flagre.FindAllStringSubmatch(pattern.Pattern, -1)
+
+		// we have a regex with flags
+		for _, match := range matches {
+			pattern.Pattern = match[1] // the inner part is our actual pattern
+			flags := match[2]          // the flags
+
+			for _, flag := range flags {
+				switch flag {
+				case 'i':
+					pattern.Pattern = `(?i)` + pattern.Pattern
+				case '!':
+					pattern.Negate = true
+				}
 			}
 		}
+
+		PatternRe, err := regexp.Compile(pattern.Pattern)
+		if err != nil {
+			return fmt.Errorf("regexp pattern %s is invalid: %w", pattern.Pattern, err)
+		}
+
+		pattern.PatternRe = PatternRe
+	}
+
+	conf.Patterns = patterns
+
+	return nil
+}
+
+// Parse config file.  Ignore if the file doesn't exist  but return an
+// error if it exists but fails to read or parse
+func (conf *Config) ParseConfigfile() error {
+	path, err := os.Stat(conf.Configfile)
+
+	if err != nil {
+		if os.IsNotExist(err) {
+			// ignore non-existent files
+			return nil
+		}
+
+		return fmt.Errorf("failed to stat config file: %w", err)
+	}
+
+	if path.IsDir() {
+		// ignore non-existent or dirs
+		return nil
+	}
+
+	configstring, err := os.ReadFile(path.Name())
+	if err != nil {
+		return fmt.Errorf("failed to read config file %s: %w", path.Name(), err)
+	}
+
+	err = hclsimple.Decode(
+		path.Name(),
+		configstring,
+		nil,
+		&conf.Settings)
+	if err != nil {
+		return fmt.Errorf("failed to load configuration file %s: %w",
+			path.Name(), err)
 	}
 
 	return nil

cfg/config_test.go

@@ -34,18 +34,18 @@ func TestPrepareModeFlags(t *testing.T) {
 		{Modeflag{O: true}, Orgtbl},
 		{Modeflag{Y: true}, Yaml},
 		{Modeflag{M: true}, Markdown},
-		{Modeflag{}, Ascii},
+		{Modeflag{}, ASCII},
 	}
 
 	// FIXME: use a map for easier printing
-	for _, tt := range tests {
-		testname := fmt.Sprintf("PrepareModeFlags-expect-%d", tt.expect)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("PrepareModeFlags-expect-%d", testdata.expect)
 		t.Run(testname, func(t *testing.T) {
-			c := Config{}
+			conf := Config{}
 
-			c.PrepareModeFlags(tt.flag)
-			if c.OutputMode != tt.expect {
-				t.Errorf("got: %d, expect: %d", c.OutputMode, tt.expect)
+			conf.PrepareModeFlags(testdata.flag)
+			if conf.OutputMode != testdata.expect {
+				t.Errorf("got: %d, expect: %d", conf.OutputMode, testdata.expect)
 			}
 		})
 	}
@@ -63,15 +63,15 @@ func TestPrepareSortFlags(t *testing.T) {
 		{Sortmode{}, "string"},
 	}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("PrepareSortFlags-expect-%s", tt.expect)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("PrepareSortFlags-expect-%s", testdata.expect)
 		t.Run(testname, func(t *testing.T) {
-			c := Config{}
+			conf := Config{}
 
-			c.PrepareSortFlags(tt.flag)
+			conf.PrepareSortFlags(testdata.flag)
 
-			if c.SortMode != tt.expect {
-				t.Errorf("got: %s, expect: %s", c.SortMode, tt.expect)
+			if conf.SortMode != testdata.expect {
+				t.Errorf("got: %s, expect: %s", conf.SortMode, testdata.expect)
 			}
 		})
 	}
@@ -79,22 +79,58 @@ func TestPrepareSortFlags(t *testing.T) {
 
 func TestPreparePattern(t *testing.T) {
 	var tests = []struct {
-		pattern string
-		wanterr bool
+		patterns  []*Pattern
+		name      string
+		wanterr   bool
+		wanticase bool
+		wantneg   bool
 	}{
-		{"[A-Z]+", false},
-		{"[a-z", true},
+		{
+			[]*Pattern{{Pattern: "[A-Z]+"}},
+			"simple",
+			false,
+			false,
+			false,
+		},
+		{
+			[]*Pattern{{Pattern: "[a-z"}},
+			"regfail",
+			true,
+			false,
+			false,
+		},
+		{
+			[]*Pattern{{Pattern: "/[A-Z]+/i"}},
+			"icase",
+			false,
+			true,
+			false,
+		},
+		{
+			[]*Pattern{{Pattern: "/[A-Z]+/!"}},
+			"negate",
+			false,
+			false,
+			true,
+		},
+		{
+			[]*Pattern{{Pattern: "/[A-Z]+/!i"}},
+			"negicase",
+			false,
+			true,
+			true,
+		},
 	}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("PreparePattern-pattern-%s-wanterr-%t", tt.pattern, tt.wanterr)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("PreparePattern-pattern-%s-wanterr-%t", testdata.name, testdata.wanterr)
 		t.Run(testname, func(t *testing.T) {
-			c := Config{}
+			conf := Config{}
 
-			err := c.PreparePattern(tt.pattern)
+			err := conf.PreparePattern(testdata.patterns)
 
 			if err != nil {
-				if !tt.wanterr {
+				if !testdata.wanterr {
 					t.Errorf("PreparePattern returned error: %s", err)
 				}
 			}

cmd/root.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2022 Thomas von Dein
+Copyright © 2022-2025 Thomas von Dein
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -33,11 +33,12 @@ import (
 func man() {
 	man := exec.Command("less", "-")
 
-	var b bytes.Buffer
-	b.Write([]byte(manpage))
+	var buffer bytes.Buffer
+
+	buffer.Write([]byte(manpage))
 
 	man.Stdout = os.Stdout
-	man.Stdin = &b
+	man.Stdin = &buffer
 	man.Stderr = os.Stderr
 
 	err := man.Run()
@@ -58,7 +59,15 @@ func completion(cmd *cobra.Command, mode string) error {
 	case "powershell":
 		return cmd.Root().GenPowerShellCompletionWithDesc(os.Stdout)
 	default:
-		return errors.New("Invalid shell parameter! Valid ones: bash|zsh|fish|powershell")
+		return errors.New("invalid shell parameter! Valid ones: bash|zsh|fish|powershell")
+	}
+}
+
+// we die with exit 1 if there's an error
+func wrapE(err error) {
+	if err != nil {
+		fmt.Println(err.Error())
+		os.Exit(1)
 	}
 }
 
@@ -76,83 +85,118 @@ func Execute() {
 		Use:   "tablizer [regex] [file, ...]",
 		Short: "[Re-]tabularize tabular data",
 		Long:  `Manipulate tabular output of other programs`,
-		RunE: func(cmd *cobra.Command, args []string) error {
+
+		Run: func(cmd *cobra.Command, args []string) {
 			if ShowVersion {
 				fmt.Println(cfg.Getversion())
-				return nil
+
+				return
 			}
 
 			if ShowManual {
 				man()
-				return nil
+
+				return
 			}
 
 			if len(ShowCompletion) > 0 {
-				return completion(cmd, ShowCompletion)
+				wrapE(completion(cmd, ShowCompletion))
+
+				return
 			}
 
 			// Setup
-			err := conf.ParseConfigfile()
-			if err != nil {
-				return err
-			}
+			wrapE(conf.ParseConfigfile())
 
 			conf.CheckEnv()
 			conf.PrepareModeFlags(modeflag)
 			conf.PrepareSortFlags(sortmode)
+
+			wrapE(conf.PrepareFilters())
+
 			conf.DetermineColormode()
 			conf.ApplyDefaults()
 
-			// setup lisp env, load plugins etc
-			err = lib.SetupLisp(&conf)
-			if err != nil {
-				return err
-			}
-
 			// actual execution starts here
-			return lib.ProcessFiles(&conf, args)
+			wrapE(lib.ProcessFiles(&conf, args))
 		},
 	}
 
 	// options
-	rootCmd.PersistentFlags().BoolVarP(&conf.Debug, "debug", "d", false, "Enable debugging")
-	rootCmd.PersistentFlags().BoolVarP(&conf.NoNumbering, "no-numbering", "n", false, "Disable header numbering")
-	rootCmd.PersistentFlags().BoolVarP(&conf.NoHeaders, "no-headers", "H", false, "Disable header display")
-	rootCmd.PersistentFlags().BoolVarP(&conf.NoColor, "no-color", "N", false, "Disable pattern highlighting")
-	rootCmd.PersistentFlags().BoolVarP(&ShowVersion, "version", "V", false, "Print program version")
-	rootCmd.PersistentFlags().BoolVarP(&conf.InvertMatch, "invert-match", "v", false, "select non-matching rows")
-	rootCmd.PersistentFlags().BoolVarP(&ShowManual, "man", "m", false, "Display manual page")
-	rootCmd.PersistentFlags().BoolVarP(&conf.UseFuzzySearch, "fuzzy", "z", false, "Use fuzzy searching")
-	rootCmd.PersistentFlags().BoolVarP(&conf.UseHighlight, "highlight-lines", "L", false, "Use alternating background colors")
-	rootCmd.PersistentFlags().StringVarP(&ShowCompletion, "completion", "", "", "Display completion code")
-	rootCmd.PersistentFlags().StringVarP(&conf.Separator, "separator", "s", cfg.DefaultSeparator, "Custom field separator")
-	rootCmd.PersistentFlags().StringVarP(&conf.Columns, "columns", "c", "", "Only show the speficied columns (separated by ,)")
+	rootCmd.PersistentFlags().BoolVarP(&conf.Debug, "debug", "d", false,
+		"Enable debugging")
+	rootCmd.PersistentFlags().BoolVarP(&conf.NoNumbering, "no-numbering", "n", false,
+		"Disable header numbering")
+	rootCmd.PersistentFlags().BoolVarP(&conf.NoHeaders, "no-headers", "H", false,
+		"Disable header display")
+	rootCmd.PersistentFlags().BoolVarP(&conf.NoColor, "no-color", "N", false,
+		"Disable pattern highlighting")
+	rootCmd.PersistentFlags().BoolVarP(&ShowVersion, "version", "V", false,
+		"Print program version")
+	rootCmd.PersistentFlags().BoolVarP(&conf.InvertMatch, "invert-match", "v", false,
+		"select non-matching rows")
+	rootCmd.PersistentFlags().BoolVarP(&ShowManual, "man", "m", false,
+		"Display manual page")
+	rootCmd.PersistentFlags().BoolVarP(&conf.UseFuzzySearch, "fuzzy", "z", false,
+		"Use fuzzy searching")
+	rootCmd.PersistentFlags().BoolVarP(&conf.UseHighlight, "highlight-lines", "L", false,
+		"Use alternating background colors")
+	rootCmd.PersistentFlags().StringVarP(&ShowCompletion, "completion", "", "",
+		"Display completion code")
+	rootCmd.PersistentFlags().StringVarP(&conf.Separator, "separator", "s", cfg.DefaultSeparator,
+		"Custom field separator")
+	rootCmd.PersistentFlags().StringVarP(&conf.Columns, "columns", "c", "",
+		"Only show the speficied columns (separated by ,)")
+	rootCmd.PersistentFlags().StringVarP(&conf.TransposeColumns, "transpose-columns", "T", "",
+		"Transpose the speficied columns (separated by ,)")
 
 	// sort options
-	rootCmd.PersistentFlags().IntVarP(&conf.SortByColumn, "sort-by", "k", 0, "Sort by column (default: 1)")
+	rootCmd.PersistentFlags().StringVarP(&conf.SortByColumn, "sort-by", "k", "",
+		"Sort by column (default: 1)")
 
 	// sort mode, only 1 allowed
-	rootCmd.PersistentFlags().BoolVarP(&conf.SortDescending, "sort-desc", "D", false, "Sort in descending order (default: ascending)")
-	rootCmd.PersistentFlags().BoolVarP(&sortmode.Numeric, "sort-numeric", "i", false, "sort according to string numerical value")
-	rootCmd.PersistentFlags().BoolVarP(&sortmode.Time, "sort-time", "t", false, "sort according to time string")
-	rootCmd.PersistentFlags().BoolVarP(&sortmode.Age, "sort-age", "a", false, "sort according to age (duration) string")
-	rootCmd.MarkFlagsMutuallyExclusive("sort-numeric", "sort-time", "sort-age")
+	rootCmd.PersistentFlags().BoolVarP(&conf.SortDescending, "sort-desc", "D", false,
+		"Sort in descending order (default: ascending)")
+	rootCmd.PersistentFlags().BoolVarP(&sortmode.Numeric, "sort-numeric", "i", false,
+		"sort according to string numerical value")
+	rootCmd.PersistentFlags().BoolVarP(&sortmode.Time, "sort-time", "t", false,
+		"sort according to time string")
+	rootCmd.PersistentFlags().BoolVarP(&sortmode.Age, "sort-age", "a", false,
+		"sort according to age (duration) string")
+	rootCmd.MarkFlagsMutuallyExclusive("sort-numeric", "sort-time",
+		"sort-age")
 
 	// output flags, only 1 allowed
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.X, "extended", "X", false, "Enable extended output")
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.M, "markdown", "M", false, "Enable markdown table output")
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.O, "orgtbl", "O", false, "Enable org-mode table output")
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.S, "shell", "S", false, "Enable shell mode output")
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.Y, "yaml", "Y", false, "Enable yaml output")
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.C, "csv", "C", false, "Enable CSV output")
-	rootCmd.PersistentFlags().BoolVarP(&modeflag.A, "ascii", "A", false, "Enable ASCII output (default)")
-	rootCmd.MarkFlagsMutuallyExclusive("extended", "markdown", "orgtbl", "shell", "yaml", "csv")
-
-	// lisp options
-	rootCmd.PersistentFlags().StringVarP(&conf.LispLoadPath, "load-path", "l", cfg.DefaultLoadPath, "Load path for lisp plugins (expects *.zy files)")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.X, "extended", "X", false,
+		"Enable extended output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.M, "markdown", "M", false,
+		"Enable markdown table output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.O, "orgtbl", "O", false,
+		"Enable org-mode table output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.S, "shell", "S", false,
+		"Enable shell mode output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.Y, "yaml", "Y", false,
+		"Enable yaml output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.C, "csv", "C", false,
+		"Enable CSV output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.A, "ascii", "A", false,
+		"Enable ASCII output (default)")
+	rootCmd.MarkFlagsMutuallyExclusive("extended", "markdown", "orgtbl",
+		"shell", "yaml", "csv")
 
 	// config file
-	rootCmd.PersistentFlags().StringVarP(&conf.Configfile, "config", "f", cfg.DefaultConfigfile, "config file (default: ~/.config/tablizer/config)")
+	rootCmd.PersistentFlags().StringVarP(&conf.Configfile, "config", "f", cfg.DefaultConfigfile,
+		"config file (default: ~/.config/tablizer/config)")
+
+	// filters
+	rootCmd.PersistentFlags().StringArrayVarP(&conf.Rawfilters,
+		"filter", "F", nil, "Filter by field (field=regexp || field!=regexp)")
+	rootCmd.PersistentFlags().StringArrayVarP(&conf.Transposers,
+		"regex-transposer", "R", nil, "apply /search/replace/ regexp to fields given in -T")
+
+	// input
+	rootCmd.PersistentFlags().StringVarP(&conf.InputFile, "read-file", "r", "",
+		"Read input data from file")
 
 	rootCmd.SetUsageTemplate(strings.TrimSpace(usage) + "\n")
 

cmd/tablizer.go

@@ -6,41 +6,44 @@ NAME
 
 SYNOPSIS
         Usage:
-          tablizer [regex] [file, ...] [flags]
+          tablizer [regex,...] [file, ...] [flags]
     
         Operational Flags:
-          -c, --columns string     Only show the speficied columns (separated by ,)
-          -v, --invert-match       select non-matching rows
-          -n, --no-numbering       Disable header numbering
-          -N, --no-color           Disable pattern highlighting
-          -H, --no-headers         Disable headers display
-          -s, --separator string   Custom field separator
-          -k, --sort-by int        Sort by column (default: 1)
-          -z, --fuzzy              Use fuzzy seach [experimental]
+          -c, --columns string              Only show the speficied columns (separated by ,)
+          -v, --invert-match                select non-matching rows
+          -n, --no-numbering                Disable header numbering
+          -N, --no-color                    Disable pattern highlighting
+          -H, --no-headers                  Disable headers display
+          -s, --separator string            Custom field separator
+          -k, --sort-by int|name            Sort by column (default: 1)
+          -z, --fuzzy                       Use fuzzy search [experimental]
+          -F, --filter field[!]=reg         Filter given field with regex, can be used multiple times
+          -T, --transpose-columns string    Transpose the speficied columns (separated by ,)
+          -R, --regex-transposer /from/to/  Apply /search/replace/ regexp to fields given in -T
 
         Output Flags (mutually exclusive):
-          -X, --extended           Enable extended output
-          -M, --markdown           Enable markdown table output
-          -O, --orgtbl             Enable org-mode table output
-          -S, --shell              Enable shell evaluable output
-          -Y, --yaml               Enable yaml output
-          -C, --csv                Enable CSV output
-          -A, --ascii              Default output mode, ascii tabular
-          -L, --hightlight-lines   Use alternating background colors for tables
+          -X, --extended                    Enable extended output
+          -M, --markdown                    Enable markdown table output
+          -O, --orgtbl                      Enable org-mode table output
+          -S, --shell                       Enable shell evaluable output
+          -Y, --yaml                        Enable yaml output
+          -C, --csv                         Enable CSV output
+          -A, --ascii                       Default output mode, ascii tabular
+          -L, --hightlight-lines            Use alternating background colors for tables
 
         Sort Mode Flags (mutually exclusive):
-          -a, --sort-age           sort according to age (duration) string
-          -D, --sort-desc          Sort in descending order (default: ascending)
-          -i, --sort-numeric       sort according to string numerical value
-          -t, --sort-time          sort according to time string
+          -a, --sort-age                    sort according to age (duration) string
+          -D, --sort-desc                   Sort in descending order (default: ascending)
+          -i, --sort-numeric                sort according to string numerical value
+          -t, --sort-time                   sort according to time string
 
         Other Flags:
-              --completion <shell> Generate the autocompletion script for <shell>
-          -f, --config <file>      Configuration file (default: ~/.config/tablizer/config)
-          -d, --debug              Enable debugging
-          -h, --help               help for tablizer
-          -m, --man                Display manual page
-          -V, --version            Print program version
+              --completion <shell>         Generate the autocompletion script for <shell>
+          -f, --config <file>              Configuration file (default: ~/.config/tablizer/config)
+          -d, --debug                      Enable debugging
+          -h, --help                       help for tablizer
+          -m, --man                        Display manual page
+          -V, --version                    Print program version
 
 DESCRIPTION
     Many programs generate tabular output. But sometimes you need to
@@ -100,10 +103,19 @@ DESCRIPTION
     highlighted. You can disable this behavior with the -N option.
 
     Use the -k option to specify by which column to sort the tabular data
-    (as in GNU sort(1)). The default sort column is the first one. To
-    disable sorting at all, supply 0 (Zero) to -k. The default sort order is
-    ascending. You can change this to descending order using the option -D.
-    The default sort order is by string, but there are other sort modes:
+    (as in GNU sort(1)). The default sort column is the first one. You can
+    specify column numbers or names. Column numbers start with 1, names are
+    case insensitive. You can specify multiple columns separated by comma to
+    sort, but the type must be the same. For example if you want to sort
+    numerically, all columns must be numbers. If you use column numbers,
+    then be aware, that these are the numbers before column extraction. For
+    example if you have a table with 4 columns and specify "-c4", then only
+    1 column (the fourth) will be printed, however if you want to sort by
+    this column, you'll have to specify "-k4".
+
+    The default sort order is ascending. You can change this to descending
+    order using the option -D. The default sort order is by alphanumeric
+    string, but there are other sort modes:
 
     -a --sort-age
         Sorts duration strings like "1d4h32m51s".
@@ -117,33 +129,63 @@ DESCRIPTION
     Finally the -d option enables debugging output which is mostly useful
     for the developer.
 
-  PATTERNS
-    You can reduce the rows being displayed by using a regular expression
-    pattern. The regexp is PCRE compatible, refer to the syntax cheat sheet
-    here: <https://github.com/google/re2/wiki/Syntax>. If you want to read a
-    more comprehensive documentation about the topic and have perl installed
-    you can read it with:
+  PATTERNS AND FILTERING
+    You can reduce the rows being displayed by using one or more regular
+    expression patterns. The regexp language being used is the one of
+    GOLANG, refer to the syntax cheat sheet here:
+    <https://pkg.go.dev/regexp/syntax>.
+
+    If you want to read a more comprehensive documentation about the topic
+    and have perl installed you can read it with:
 
         perldoc perlre
 
-    Or read it online: <https://perldoc.perl.org/perlre>.
+    Or read it online: <https://perldoc.perl.org/perlre>. But please note
+    that the GO regexp engine does NOT support all perl regex terms,
+    especially look-ahead and look-behind.
 
-    A note on modifiers: the regexp engine used in tablizer uses another
-    modifier syntax:
+    If you want to supply flags to a regex, then surround it with slashes
+    and append the flag. The following flags are supported:
 
-        (?MODIFIER)
-
-    The most important modifiers are:
-
-    "i" ignore case "m" multiline mode "s" single line mode
+        i => case insensitive
+        ! => negative match
 
     Example for a case insensitive search:
 
-        kubectl get pods -A | tablizer "(?i)account"
+        kubectl get pods -A | tablizer "/account/i"
 
-    You can use the experimental fuzzy seach feature by providing the option
-    -z, in which case the pattern is regarded as a fuzzy search term, not a
-    regexp.
+    If you use the "!" flag, then the regex match will be negated, that is,
+    if a line in the input matches the given regex, but "!" is supplied,
+    tablizer will NOT include it in the output.
+
+    For example, here we want to get all lines matching "foo" but not "bar":
+
+        cat table | tablizer foo '/bar/!'
+
+    This would match a line "foo zorro" but not "foo bar".
+
+    The flags can also be combined.
+
+    You can also use the experimental fuzzy search feature by providing the
+    option -z, in which case the pattern is regarded as a fuzzy search term,
+    not a regexp.
+
+    Sometimes you want to filter by one or more columns. You can do that
+    using the -F option. The option can be specified multiple times and has
+    the following format:
+
+        fieldname=regexp
+
+    Fieldnames (== columns headers) are case insensitive.
+
+    If you specify more than one filter, both filters have to match (AND
+    operation).
+
+    These field filters can also be negated:
+
+        fieldname!=regexp
+
+    If the option -v is specified, the filtering is inverted.
 
   COLUMNS
     The parameter -c can be used to specify, which columns to display. By
@@ -171,6 +213,44 @@ DESCRIPTION
 
     where "C" is our regexp which matches CMD.
 
+    If a column specifier doesn't look like a regular expression, matching
+    against header fields will be case insensitive. So, if you have a field
+    with the name "ID" then these will all match: "-c id", "-c Id". The same
+    rule applies to the options "-T" and "-F".
+
+  TRANSPOSE FIELDS USING REGEXPS
+    You can manipulate field contents using regular expressions. You have to
+    tell tablizer which field[s] to operate on using the option "-T" and the
+    search/replace pattern using "-R". The number of columns and patterns
+    must match.
+
+    A search/replace pattern consists of the following elements:
+
+        /search-regexp/replace-string/
+
+    The separator can be any valid character. Especially if you want to use
+    a regexp containing the "/" character, eg:
+
+        |search-regexp|replace-string|
+
+    Example:
+
+        cat t/testtable2
+        NAME  DURATION
+        x     10
+        a     100
+        z     0
+        u     4
+        k     6
+    
+        cat t/testtable2 | tablizer -T2 -R '/^\d/4/' -n
+        NAME    DURATION 
+        x       40      
+        a       400     
+        z       4       
+        u       4       
+        k       4
+
   OUTPUT MODES
     There might be cases when the tabular output of a program is way too
     large for your current terminal but you still need to see every column.
@@ -298,7 +378,7 @@ LICENSE
     This software is licensed under the GNU GENERAL PUBLIC LICENSE version
     3.
 
-    Copyright (c) 2023 by Thomas von Dein
+    Copyright (c) 2022-2024 by Thomas von Dein
 
     This software uses the following GO modules:
 
@@ -329,41 +409,44 @@ AUTHORS
 var usage = `
 
 Usage:
-  tablizer [regex] [file, ...] [flags]
+  tablizer [regex,...] [file, ...] [flags]
 
 Operational Flags:
-  -c, --columns string     Only show the speficied columns (separated by ,)
-  -v, --invert-match       select non-matching rows
-  -n, --no-numbering       Disable header numbering
-  -N, --no-color           Disable pattern highlighting
-  -H, --no-headers         Disable headers display
-  -s, --separator string   Custom field separator
-  -k, --sort-by int        Sort by column (default: 1)
-  -z, --fuzzy              Use fuzzy seach [experimental]
+  -c, --columns string              Only show the speficied columns (separated by ,)
+  -v, --invert-match                select non-matching rows
+  -n, --no-numbering                Disable header numbering
+  -N, --no-color                    Disable pattern highlighting
+  -H, --no-headers                  Disable headers display
+  -s, --separator string            Custom field separator
+  -k, --sort-by int|name            Sort by column (default: 1)
+  -z, --fuzzy                       Use fuzzy search [experimental]
+  -F, --filter field[!]=reg         Filter given field with regex, can be used multiple times
+  -T, --transpose-columns string    Transpose the speficied columns (separated by ,)
+  -R, --regex-transposer /from/to/  Apply /search/replace/ regexp to fields given in -T
 
 Output Flags (mutually exclusive):
-  -X, --extended           Enable extended output
-  -M, --markdown           Enable markdown table output
-  -O, --orgtbl             Enable org-mode table output
-  -S, --shell              Enable shell evaluable output
-  -Y, --yaml               Enable yaml output
-  -C, --csv                Enable CSV output
-  -A, --ascii              Default output mode, ascii tabular
-  -L, --hightlight-lines   Use alternating background colors for tables
+  -X, --extended                    Enable extended output
+  -M, --markdown                    Enable markdown table output
+  -O, --orgtbl                      Enable org-mode table output
+  -S, --shell                       Enable shell evaluable output
+  -Y, --yaml                        Enable yaml output
+  -C, --csv                         Enable CSV output
+  -A, --ascii                       Default output mode, ascii tabular
+  -L, --hightlight-lines            Use alternating background colors for tables
 
 Sort Mode Flags (mutually exclusive):
-  -a, --sort-age           sort according to age (duration) string
-  -D, --sort-desc          Sort in descending order (default: ascending)
-  -i, --sort-numeric       sort according to string numerical value
-  -t, --sort-time          sort according to time string
+  -a, --sort-age                    sort according to age (duration) string
+  -D, --sort-desc                   Sort in descending order (default: ascending)
+  -i, --sort-numeric                sort according to string numerical value
+  -t, --sort-time                   sort according to time string
 
 Other Flags:
-      --completion <shell> Generate the autocompletion script for <shell>
-  -f, --config <file>      Configuration file (default: ~/.config/tablizer/config)
-  -d, --debug              Enable debugging
-  -h, --help               help for tablizer
-  -m, --man                Display manual page
-  -V, --version            Print program version
+      --completion <shell>         Generate the autocompletion script for <shell>
+  -f, --config <file>              Configuration file (default: ~/.config/tablizer/config)
+  -d, --debug                      Enable debugging
+  -h, --help                       help for tablizer
+  -m, --man                        Display manual page
+  -V, --version                    Print program version
 
 
 `

go.mod

@@ -1,43 +1,34 @@
 module github.com/tlinden/tablizer
 
-go 1.18
+go 1.22
 
 require (
-	github.com/alecthomas/repr v0.1.1
+	github.com/alecthomas/repr v0.4.0
 	github.com/araddon/dateparse v0.0.0-20210429162001-6b43995a97de
-	github.com/glycerine/zygomys v5.1.2+incompatible
-	github.com/gookit/color v1.5.2
-	github.com/hashicorp/hcl/v2 v2.19.1
-	github.com/lithammer/fuzzysearch v1.1.7
+	github.com/gookit/color v1.5.4
+	github.com/hashicorp/hcl/v2 v2.23.0
+	github.com/lithammer/fuzzysearch v1.1.8
 	github.com/olekukonko/tablewriter v0.0.5
-	github.com/spf13/cobra v1.6.1
+	github.com/rogpeppe/go-internal v1.13.1
+	github.com/spf13/cobra v1.8.1
 	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
-	github.com/agext/levenshtein v1.2.1 // indirect
+	github.com/agext/levenshtein v1.2.3 // indirect
 	github.com/apparentlymart/go-textseg/v13 v13.0.0 // indirect
 	github.com/apparentlymart/go-textseg/v15 v15.0.0 // indirect
-	github.com/glycerine/blake2b v0.0.0-20151022103502-3c8c640cd7be // indirect
-	github.com/glycerine/goconvey v0.0.0-20190410193231-58a59202ab31 // indirect
-	github.com/glycerine/greenpack v5.1.1+incompatible // indirect
-	github.com/glycerine/liner v0.0.0-20160121172638-72909af234e0 // indirect
-	github.com/google/go-cmp v0.5.6 // indirect
-	github.com/gopherjs/gopherjs v1.17.2 // indirect
-	github.com/inconshreveable/mousetrap v1.0.1 // indirect
-	github.com/jtolds/gls v4.20.0+incompatible // indirect
-	github.com/mattn/go-runewidth v0.0.10 // indirect
+	github.com/google/go-cmp v0.6.0 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/mattn/go-runewidth v0.0.16 // indirect
 	github.com/mitchellh/go-wordwrap v0.0.0-20150314170334-ad45545899c7 // indirect
-	github.com/philhofer/fwd v1.1.2 // indirect
-	github.com/rivo/uniseg v0.1.0 // indirect
-	github.com/shurcooL/go v0.0.0-20200502201357-93f07166e636 // indirect
-	github.com/shurcooL/go-goon v1.0.0 // indirect
+	github.com/rivo/uniseg v0.2.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
-	github.com/tinylib/msgp v1.1.9 // indirect
-	github.com/ugorji/go/codec v1.2.11 // indirect
-	github.com/xo/terminfo v0.0.0-20210125001918-ca9a967f8778 // indirect
-	github.com/zclconf/go-cty v1.13.0 // indirect
-	golang.org/x/sys v0.13.0 // indirect
+	github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e // indirect
+	github.com/zclconf/go-cty v1.13.3 // indirect
+	golang.org/x/mod v0.18.0 // indirect
+	golang.org/x/sync v0.7.0 // indirect
+	golang.org/x/sys v0.21.0 // indirect
 	golang.org/x/text v0.11.0 // indirect
-	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
+	golang.org/x/tools v0.22.0 // indirect
 )

go.sum

@@ -1,88 +1,69 @@
-github.com/agext/levenshtein v1.2.1 h1:QmvMAjj2aEICytGiWzmxoE0x2KZvE0fvmqMOfy2tjT8=
-github.com/agext/levenshtein v1.2.1/go.mod h1:JEDfjyjHDjOF/1e4FlBE/PkbqA9OfWu2ki2W0IB5558=
-github.com/alecthomas/repr v0.1.1 h1:87P60cSmareLAxMc4Hro0r2RBY4ROm0dYwkJNpS4pPs=
-github.com/alecthomas/repr v0.1.1/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
+github.com/agext/levenshtein v1.2.3 h1:YB2fHEn0UJagG8T1rrWknE3ZQzWM06O8AMAatNn7lmo=
+github.com/agext/levenshtein v1.2.3/go.mod h1:JEDfjyjHDjOF/1e4FlBE/PkbqA9OfWu2ki2W0IB5558=
+github.com/alecthomas/repr v0.4.0 h1:GhI2A8MACjfegCPVq9f1FLvIBS+DrQ2KQBFZP1iFzXc=
+github.com/alecthomas/repr v0.4.0/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
 github.com/apparentlymart/go-textseg/v13 v13.0.0 h1:Y+KvPE1NYz0xl601PVImeQfFyEy6iT90AvPUL1NNfNw=
 github.com/apparentlymart/go-textseg/v13 v13.0.0/go.mod h1:ZK2fH7c4NqDTLtiYLvIkEghdlcqw7yxLeM89kiTRPUo=
 github.com/apparentlymart/go-textseg/v15 v15.0.0 h1:uYvfpb3DyLSCGWnctWKGj857c6ew1u1fNQOlOtuGxQY=
 github.com/apparentlymart/go-textseg/v15 v15.0.0/go.mod h1:K8XmNZdhEBkdlyDdvbmmsvpAG721bKi0joRfFdHIWJ4=
 github.com/araddon/dateparse v0.0.0-20210429162001-6b43995a97de h1:FxWPpzIjnTlhPwqqXc4/vE0f7GvRjuAsbW+HOIe8KnA=
 github.com/araddon/dateparse v0.0.0-20210429162001-6b43995a97de/go.mod h1:DCaWoUhZrYW9p1lxo/cm8EmUOOzAPSEZNGF2DK1dJgw=
-github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/cpuguy83/go-md2man/v2 v2.0.4/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/glycerine/blake2b v0.0.0-20151022103502-3c8c640cd7be h1:XBJdPGgA3qqhW+p9CANCAVdF7ZIXdu3pZAkypMkKAjE=
-github.com/glycerine/blake2b v0.0.0-20151022103502-3c8c640cd7be/go.mod h1:OSCrScrFAjcBObrulk6BEQlytA462OkG1UGB5NYj9kE=
-github.com/glycerine/goconvey v0.0.0-20190410193231-58a59202ab31 h1:gclg6gY70GLy3PbkQ1AERPfmLMMagS60DKF78eWwLn8=
-github.com/glycerine/goconvey v0.0.0-20190410193231-58a59202ab31/go.mod h1:Ogl1Tioa0aV7gstGFO7KhffUsb9M4ydbEbbxpcEDc24=
-github.com/glycerine/greenpack v5.1.1+incompatible h1:fDr9i6MkSGZmAy4VXPfJhW+SyK2/LNnzIp5nHyDiaIM=
-github.com/glycerine/greenpack v5.1.1+incompatible/go.mod h1:us0jVISAESGjsEuLlAfCd5nkZm6W6WQF18HPuOecIg4=
-github.com/glycerine/liner v0.0.0-20160121172638-72909af234e0 h1:4ZegphJXBTc4uFQ08UVoWYmQXorGa+ipXetUj83sMBc=
-github.com/glycerine/liner v0.0.0-20160121172638-72909af234e0/go.mod h1:AqJLs6UeoC65dnHxyCQ6MO31P5STpjcmgaANAU+No8Q=
-github.com/glycerine/zygomys v5.1.2+incompatible h1:jmcdmA3XPxgfOunAXFpipE9LQoUL6eX6d2mhYyjV4GE=
-github.com/glycerine/zygomys v5.1.2+incompatible/go.mod h1:i3SPKZpmy9dwF/3iWrXJ/ZLyzZucegwypwOmqRkUUaQ=
 github.com/go-test/deep v1.0.3 h1:ZrJSEWsXzPOxaZnFteGEfooLba+ju3FYIbOrS+rQd68=
-github.com/google/go-cmp v0.5.6 h1:BKbKCqvP6I+rmFHt06ZmyQtvB8xAkWdhFyr0ZUNZcxQ=
-github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/gookit/color v1.5.2 h1:uLnfXcaFjlrDnQDT+NCBcfhrXqYTx/rcCa6xn01Y8yI=
-github.com/gookit/color v1.5.2/go.mod h1:w8h4bGiHeeBpvQVePTutdbERIUf3oJE5lZ8HM0UgXyg=
-github.com/gopherjs/gopherjs v1.17.2 h1:fQnZVsXk8uxXIStYb0N4bGk7jeyTalG/wsZjQ25dO0g=
-github.com/gopherjs/gopherjs v1.17.2/go.mod h1:pRRIvn/QzFLrKfvEz3qUuEhtE/zLCWfreZ6J5gM2i+k=
-github.com/hashicorp/hcl/v2 v2.19.1 h1://i05Jqznmb2EXqa39Nsvyan2o5XyMowW5fnCKW5RPI=
-github.com/hashicorp/hcl/v2 v2.19.1/go.mod h1:ThLC89FV4p9MPW804KVbe/cEXoQ8NZEh+JtMeeGErHE=
-github.com/inconshreveable/mousetrap v1.0.1 h1:U3uMjPSQEBMNp1lFxmllqCPM6P5u/Xq7Pgzkat/bFNc=
-github.com/inconshreveable/mousetrap v1.0.1/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
-github.com/jtolds/gls v4.20.0+incompatible h1:xdiiI2gbIgH/gLH7ADydsJ1uDOEzR8yvV7C0MuV77Wo=
-github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
-github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
-github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
-github.com/kylelemons/godebug v0.0.0-20170820004349-d65d576e9348 h1:MtvEpTB6LX3vkb4ax0b5D2DHbNAUsen0Gx5wZoq3lV4=
-github.com/lithammer/fuzzysearch v1.1.7 h1:q8rZNmBIUkqxsxb/IlwsXVbCoPIH/0juxjFHY0UIwhU=
-github.com/lithammer/fuzzysearch v1.1.7/go.mod h1:ZhIlfRGxnD8qa9car/yplC6GmnM14CS07BYAKJJBK2I=
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+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
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 github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
-github.com/mattn/go-runewidth v0.0.10 h1:CoZ3S2P7pvtP45xOtBw+/mDL2z0RKI576gSkzRRpdGg=
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 github.com/mitchellh/go-wordwrap v0.0.0-20150314170334-ad45545899c7 h1:DpOJ2HYzCv8LZP15IdmG+YdwD2luVPHITV96TkirNBM=
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-github.com/philhofer/fwd v1.1.2 h1:bnDivRJ1EWPjUIRXV5KfORO897HTbpFAQddBdE8t7Gw=
-github.com/philhofer/fwd v1.1.2/go.mod h1:qkPdfjR2SIEbspLqpe1tO4n5yICnr2DY7mqEx2tUTP0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
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-github.com/rivo/uniseg v0.1.0 h1:+2KBaVoUmb9XzDsrx/Ct0W/EYOSFf/nWTauy++DprtY=
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+github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
+github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/scylladb/termtables v0.0.0-20191203121021-c4c0b6d42ff4/go.mod h1:C1a7PQSMz9NShzorzCiG2fk9+xuCgLkPeCvMHYR2OWg=
-github.com/sergi/go-diff v1.0.0 h1:Kpca3qRNrduNnOQeazBd0ysaKrUJiIuISHxogkT9RPQ=
-github.com/shurcooL/go v0.0.0-20200502201357-93f07166e636 h1:aSISeOcal5irEhJd1M+IrApc0PdcN7e7Aj4yuEnOrfQ=
-github.com/shurcooL/go v0.0.0-20200502201357-93f07166e636/go.mod h1:TDJrrUr11Vxrven61rcy3hJMUqaf/CLWYhHNPmT14Lk=
-github.com/shurcooL/go-goon v1.0.0 h1:BCQPvxGkHHJ4WpBO4m/9FXbITVIsvAm/T66cCcCGI7E=
-github.com/shurcooL/go-goon v1.0.0/go.mod h1:2wTHMsGo7qnpmqA8ADYZtP4I1DD94JpXGQ3Dxq2YQ5w=
-github.com/spf13/cobra v1.6.1 h1:o94oiPyS4KD1mPy2fmcYYHHfCxLqYjJOhGsCHFZtEzA=
-github.com/spf13/cobra v1.6.1/go.mod h1:IOw/AERYS7UzyrGinqmz6HLUo219MORXGxhbaJUqzrY=
+github.com/spf13/cobra v1.8.1 h1:e5/vxKd/rZsfSJMUX1agtjeTDf+qv1/JdBF8gg5k9ZM=
+github.com/spf13/cobra v1.8.1/go.mod h1:wHxEcudfqmLYa8iTfL+OuZPbBZkmvliBWKIezN3kD9Y=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
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-github.com/tinylib/msgp v1.1.9 h1:SHf3yoO2sGA0veCJeCBYLHuttAVFHGm2RHgNodW7wQU=
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-github.com/ugorji/go/codec v1.2.11/go.mod h1:UNopzCgEMSXjBc6AOMqYvWC1ktqTAfzJZUZgYf6w6lg=
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-github.com/xo/terminfo v0.0.0-20210125001918-ca9a967f8778/go.mod h1:2MuV+tbUrU1zIOPMxZ5EncGwgmMJsa+9ucAQZXxsObs=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
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 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-github.com/zclconf/go-cty v1.13.0 h1:It5dfKTTZHe9aeppbNOda3mN7Ag7sg6QkBNm6TkyFa0=
-github.com/zclconf/go-cty v1.13.0/go.mod h1:YKQzy/7pZ7iq2jNFzy5go57xdxdWoLLpaEp4u238AE0=
+github.com/zclconf/go-cty v1.13.3 h1:m+b9q3YDbg6Bec5rr+KGy1MzEVzY/jC2X+YX4yqKtHI=
+github.com/zclconf/go-cty v1.13.3/go.mod h1:YKQzy/7pZ7iq2jNFzy5go57xdxdWoLLpaEp4u238AE0=
+github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940 h1:4r45xpDWB6ZMSMNJFMOjqrGHynW3DIBuR2H9j0ug+Mo=
+github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940/go.mod h1:CmBdvvj3nqzfzJ6nTCIwDTPZ56aVGvDrmztiO5g3qrM=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
+golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561 h1:MDc5xs78ZrZr3HMQugiXOAkSZtfTpbJLDr/lwfgO53E=
+golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561/go.mod h1:cyybsKvd6eL0RnXn6p/Grxp8F5bW7iYuBgsNCOHpMYE=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/mod v0.18.0 h1:5+9lSbEzPSdWkH32vYPBwEpX8KwDbM52Ud9xBUvNlb0=
+golang.org/x/mod v0.18.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
@@ -90,15 +71,16 @@ golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
+golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.13.0 h1:Af8nKPmuFypiUBjVoU9V20FiaFXOcuZI21p0ycVYYGE=
-golang.org/x/sys v0.13.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.21.0 h1:rF+pYz3DAGSQAxAu1CbC7catZg4ebC4UIeIhKxBZvws=
+golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
@@ -106,17 +88,16 @@ golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.8.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
+golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
 golang.org/x/text v0.11.0 h1:LAntKIrcmeSKERyiOh0XMV39LXS8IE9UL2yP7+f5ij4=
 golang.org/x/text v0.11.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
+golang.org/x/tools v0.22.0 h1:gqSGLZqv+AI9lIQzniJ0nZDRG5GBPsSi+DRNHWNz6yA=
+golang.org/x/tools v0.22.0/go.mod h1:aCwcsjqvq7Yqt6TNyX7QMU2enbQ/Gt0bo6krSeEri+c=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

lib/common.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2022 Thomas von Dein
+Copyright © 2022-2024 Thomas von Dein
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -24,3 +24,13 @@ type Tabdata struct {
 	headers        []string // [ "ID", "NAME", ...]
 	entries        [][]string
 }
+
+func (data *Tabdata) CloneEmpty() Tabdata {
+	newdata := Tabdata{
+		maxwidthHeader: data.maxwidthHeader,
+		columns:        data.columns,
+		headers:        data.headers,
+	}
+
+	return newdata
+}

lib/filter.go

@@ -0,0 +1,192 @@
+/*
+Copyright © 2022-2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package lib
+
+import (
+	"bufio"
+	"io"
+	"strings"
+
+	"github.com/lithammer/fuzzysearch/fuzzy"
+	"github.com/tlinden/tablizer/cfg"
+)
+
+/*
+* [!]Match a  line, use fuzzy  search for normal pattern  strings and
+* regexp otherwise.
+
+		'foo bar'  foo, /bar/!  => false => line contains foo and not (not bar)
+	    'foo nix'  foo, /bar/!  => ture  => line contains foo and (not bar)
+		'foo bar'  foo, /bar/   => true  => line contains both foo and bar
+		'foo nix'  foo, /bar/   => false => line does not contain bar
+		'foo bar'  foo, /nix/   => false => line does not contain nix
+*/
+func matchPattern(conf cfg.Config, line string) bool {
+	if len(conf.Patterns) == 0 {
+		// any line always matches ""
+		return true
+	}
+
+	if conf.UseFuzzySearch {
+		// fuzzy search only considers the 1st pattern
+		return fuzzy.MatchFold(conf.Patterns[0].Pattern, line)
+	}
+
+	var match int
+
+	//fmt.Printf("<%s>\n", line)
+	for _, re := range conf.Patterns {
+		patmatch := re.PatternRe.MatchString(line)
+		if re.Negate {
+			// toggle the meaning of match
+			patmatch = !patmatch
+		}
+
+		if patmatch {
+			match++
+		}
+
+		//fmt.Printf("patmatch: %t, match: %d, pattern: %s, negate: %t\n", patmatch, match, re.Pattern, re.Negate)
+	}
+
+	// fmt.Printf("result: %t\n", match == len(conf.Patterns))
+	//fmt.Println()
+	return match == len(conf.Patterns)
+}
+
+/*
+ * Filter parsed data by fields. The  filter is positive, so if one or
+ * more filters match on a row, it  will be kept, otherwise it will be
+ * excluded.
+ */
+func FilterByFields(conf cfg.Config, data *Tabdata) (*Tabdata, bool, error) {
+	if len(conf.Filters) == 0 {
+		// no filters, no checking
+		return nil, false, nil
+	}
+
+	newdata := data.CloneEmpty()
+
+	for _, row := range data.entries {
+		keep := true
+
+		for idx, header := range data.headers {
+			lcheader := strings.ToLower(header)
+			if !Exists(conf.Filters, lcheader) {
+				// do not filter by unspecified field
+				continue
+			}
+
+			match := conf.Filters[lcheader].Regex.MatchString(row[idx])
+			if conf.Filters[lcheader].Negate {
+				match = !match
+			}
+
+			if !match {
+				keep = false
+				break
+			}
+		}
+
+		if keep == !conf.InvertMatch {
+			// also apply -v
+			newdata.entries = append(newdata.entries, row)
+		}
+	}
+
+	return &newdata, true, nil
+}
+
+/*
+ * Transpose fields using search/replace regexp.
+ */
+func TransposeFields(conf cfg.Config, data *Tabdata) (*Tabdata, bool, error) {
+	if len(conf.UseTransposers) == 0 {
+		// nothing to be done
+		return nil, false, nil
+	}
+
+	newdata := data.CloneEmpty()
+	transposed := false
+
+	for _, row := range data.entries {
+		transposedrow := false
+
+		for idx := range data.headers {
+			transposeidx, hasone := findindex(conf.UseTransposeColumns, idx+1)
+			if hasone {
+				row[idx] =
+					conf.UseTransposers[transposeidx].Search.ReplaceAllString(
+						row[idx],
+						conf.UseTransposers[transposeidx].Replace,
+					)
+				transposedrow = true
+			}
+		}
+
+		if transposedrow {
+			// also apply -v
+			newdata.entries = append(newdata.entries, row)
+			transposed = true
+		}
+	}
+
+	return &newdata, transposed, nil
+}
+
+/* generic map.Exists(key) */
+func Exists[K comparable, V any](m map[K]V, v K) bool {
+	if _, ok := m[v]; ok {
+		return true
+	}
+
+	return false
+}
+
+/*
+ * Filters the whole input lines, returns filtered lines
+ */
+func FilterByPattern(conf cfg.Config, input io.Reader) (io.Reader, error) {
+	if len(conf.Patterns) == 0 {
+		return input, nil
+	}
+
+	scanner := bufio.NewScanner(input)
+	lines := []string{}
+	hadFirst := false
+
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if hadFirst {
+			// don't match 1st line, it's the header
+			if matchPattern(conf, line) == conf.InvertMatch {
+				// by default  -v is false, so if a  line does NOT
+				// match the pattern, we will ignore it. However,
+				// if the user specified -v, the matching is inverted,
+				// so we ignore all lines, which DO match.
+				continue
+			}
+		}
+
+		lines = append(lines, line)
+
+		hadFirst = true
+	}
+
+	return strings.NewReader(strings.Join(lines, "\n")), nil
+}

lib/filter_test.go

@@ -0,0 +1,176 @@
+/*
+Copyright © 2024-2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package lib
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"github.com/tlinden/tablizer/cfg"
+)
+
+func TestMatchPattern(t *testing.T) {
+	var input = []struct {
+		name     string
+		fuzzy    bool
+		patterns []*cfg.Pattern
+		line     string
+	}{
+		{
+			name:     "normal",
+			patterns: []*cfg.Pattern{{Pattern: "haus"}},
+			line:     "hausparty",
+		},
+		{
+			name:     "fuzzy",
+			patterns: []*cfg.Pattern{{Pattern: "hpt"}},
+			line:     "haus-party-termin",
+			fuzzy:    true,
+		},
+	}
+
+	for _, inputdata := range input {
+		testname := fmt.Sprintf("match-pattern-%s", inputdata.name)
+
+		t.Run(testname, func(t *testing.T) {
+			conf := cfg.Config{}
+
+			if inputdata.fuzzy {
+				conf.UseFuzzySearch = true
+			}
+
+			err := conf.PreparePattern(inputdata.patterns)
+			if err != nil {
+				t.Errorf("PreparePattern returned error: %s", err)
+			}
+
+			if !matchPattern(conf, inputdata.line) {
+				t.Errorf("matchPattern() did not match\nExp: true\nGot: false\n")
+			}
+		})
+	}
+}
+
+func TestFilterByFields(t *testing.T) {
+	data := Tabdata{
+		headers: []string{
+			"ONE", "TWO", "THREE",
+		},
+		entries: [][]string{
+			{"asd", "igig", "cxxxncnc"},
+			{"19191", "EDD 1", "x"},
+			{"8d8", "AN 1", "y"},
+		},
+	}
+
+	var input = []struct {
+		name   string
+		filter []string
+		expect Tabdata
+		invert bool
+	}{
+		{
+			name:   "one-field",
+			filter: []string{"one=19"},
+			expect: Tabdata{
+				headers: []string{
+					"ONE", "TWO", "THREE",
+				},
+				entries: [][]string{
+					{"19191", "EDD 1", "x"},
+				},
+			},
+		},
+
+		{
+			name:   "one-field-negative",
+			filter: []string{"one!=asd"},
+			expect: Tabdata{
+				headers: []string{
+					"ONE", "TWO", "THREE",
+				},
+				entries: [][]string{
+					{"19191", "EDD 1", "x"},
+					{"8d8", "AN 1", "y"},
+				},
+			},
+		},
+
+		{
+			name:   "one-field-inverted",
+			filter: []string{"one=19"},
+			invert: true,
+			expect: Tabdata{
+				headers: []string{
+					"ONE", "TWO", "THREE",
+				},
+				entries: [][]string{
+					{"asd", "igig", "cxxxncnc"},
+					{"8d8", "AN 1", "y"},
+				},
+			},
+		},
+
+		{
+			name:   "many-fields",
+			filter: []string{"one=19", "two=DD"},
+			expect: Tabdata{
+				headers: []string{
+					"ONE", "TWO", "THREE",
+				},
+				entries: [][]string{
+					{"19191", "EDD 1", "x"},
+				},
+			},
+		},
+
+		{
+			name:   "many-fields-inverted",
+			filter: []string{"one=19", "two=DD"},
+			invert: true,
+			expect: Tabdata{
+				headers: []string{
+					"ONE", "TWO", "THREE",
+				},
+				entries: [][]string{
+					{"asd", "igig", "cxxxncnc"},
+					{"8d8", "AN 1", "y"},
+				},
+			},
+		},
+	}
+
+	for _, inputdata := range input {
+		testname := fmt.Sprintf("filter-by-fields-%s", inputdata.name)
+
+		t.Run(testname, func(t *testing.T) {
+			conf := cfg.Config{Rawfilters: inputdata.filter, InvertMatch: inputdata.invert}
+
+			err := conf.PrepareFilters()
+			if err != nil {
+				t.Errorf("PrepareFilters returned error: %s", err)
+			}
+
+			data, _, _ := FilterByFields(conf, &data)
+			if !reflect.DeepEqual(*data, inputdata.expect) {
+				t.Errorf("Filtered data does not match expected data:\ngot: %+v\nexp: %+v", data, inputdata.expect)
+			}
+		})
+	}
+}

lib/helpers.go

@@ -36,79 +36,175 @@ func contains(s []int, e int) bool {
 			return true
 		}
 	}
+
 	return false
 }
 
-// parse columns list given  with -c, modifies config.UseColumns based
-// on eventually given regex
-func PrepareColumns(c *cfg.Config, data *Tabdata) error {
-	if len(c.Columns) > 0 {
-		for _, use := range strings.Split(c.Columns, ",") {
-			if len(use) == 0 {
-				msg := fmt.Sprintf("Could not parse columns list %s: empty column", c.Columns)
-				return errors.New(msg)
-			}
-
-			usenum, err := strconv.Atoi(use)
-			if err != nil {
-				// might be a regexp
-				colPattern, err := regexp.Compile(use)
-				if err != nil {
-					msg := fmt.Sprintf("Could not parse columns list %s: %v", c.Columns, err)
-					return errors.New(msg)
-				}
-
-				// find matching header fields
-				for i, head := range data.headers {
-					if colPattern.MatchString(head) {
-						c.UseColumns = append(c.UseColumns, i+1)
-					}
-
-				}
-			} else {
-				// we digress from go  best practises here, because if
-				// a colum spec is not a number, we process them above
-				// inside the err handler  for atoi(). so only add the
-				// number, if it's really just a number.
-				c.UseColumns = append(c.UseColumns, usenum)
-			}
+func findindex(s []int, e int) (int, bool) {
+	for i, a := range s {
+		if a == e {
+			return i, true
 		}
-
-		// deduplicate: put all values into a map (value gets map key)
-		// thereby  removing duplicates,  extract keys into  new slice
-		// and sort it
-		imap := make(map[int]int, len(c.UseColumns))
-		for _, i := range c.UseColumns {
-			imap[i] = 0
-		}
-		c.UseColumns = nil
-		for k := range imap {
-			c.UseColumns = append(c.UseColumns, k)
-		}
-		sort.Ints(c.UseColumns)
 	}
+
+	return 0, false
+}
+
+// validate the consitency of parsed data
+func ValidateConsistency(data *Tabdata) error {
+	expectedfields := len(data.headers)
+
+	for idx, row := range data.entries {
+		if len(row) != expectedfields {
+			return fmt.Errorf("row %d does not contain expected %d elements, but %d",
+				idx, expectedfields, len(row))
+		}
+	}
+
 	return nil
 }
 
+// parse columns list given  with -c, modifies config.UseColumns based
+// on eventually given regex.
+// This is an output filter, because -cN,N,... is being applied AFTER
+// processing of the input data.
+func PrepareColumns(conf *cfg.Config, data *Tabdata) error {
+	// -c columns
+	usecolumns, err := PrepareColumnVars(conf.Columns, data)
+	if err != nil {
+		return err
+	}
+
+	conf.UseColumns = usecolumns
+
+	return nil
+}
+
+// Same thing as above but for -T option, which is an input option,
+// because transposers are being applied before output.
+func PrepareTransposerColumns(conf *cfg.Config, data *Tabdata) error {
+	// -T columns
+	usetransposecolumns, err := PrepareColumnVars(conf.TransposeColumns, data)
+	if err != nil {
+		return err
+	}
+
+	conf.UseTransposeColumns = usetransposecolumns
+
+	// verify that columns and transposers match and prepare transposer structs
+	if err := conf.PrepareTransposers(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// output option, prepare -k1,2 sort fields
+func PrepareSortColumns(conf *cfg.Config, data *Tabdata) error {
+	// -c columns
+	usecolumns, err := PrepareColumnVars(conf.SortByColumn, data)
+	if err != nil {
+		return err
+	}
+
+	conf.UseSortByColumn = usecolumns
+
+	return nil
+}
+
+func PrepareColumnVars(columns string, data *Tabdata) ([]int, error) {
+	if columns == "" {
+		return nil, nil
+	}
+
+	usecolumns := []int{}
+
+	isregex := regexp.MustCompile(`\W`)
+
+	for _, columnpattern := range strings.Split(columns, ",") {
+		if len(columnpattern) == 0 {
+			return nil, fmt.Errorf("could not parse columns list %s: empty column", columns)
+		}
+
+		usenum, err := strconv.Atoi(columnpattern)
+		if err != nil {
+			// not a number
+
+			if !isregex.MatchString(columnpattern) {
+				// is not a regexp (contains no non-word chars)
+				// lc() it so that word searches are case insensitive
+				columnpattern = strings.ToLower(columnpattern)
+
+				for i, head := range data.headers {
+					if columnpattern == strings.ToLower(head) {
+						usecolumns = append(usecolumns, i+1)
+					}
+				}
+			} else {
+				colPattern, err := regexp.Compile("(?i)" + columnpattern)
+				if err != nil {
+					msg := fmt.Sprintf("Could not parse columns list %s: %v", columns, err)
+
+					return nil, errors.New(msg)
+				}
+
+				// find matching header fields, ignoring case
+				for i, head := range data.headers {
+					if colPattern.MatchString(strings.ToLower(head)) {
+						usecolumns = append(usecolumns, i+1)
+					}
+				}
+			}
+		} else {
+			// we digress from go  best practises here, because if
+			// a colum spec is not a number, we process them above
+			// inside the err handler  for atoi(). so only add the
+			// number, if it's really just a number.
+			usecolumns = append(usecolumns, usenum)
+		}
+	}
+
+	// deduplicate: put all values into a map (value gets map key)
+	// thereby  removing duplicates,  extract keys into  new slice
+	// and sort it
+	imap := make(map[int]int, len(usecolumns))
+	for _, i := range usecolumns {
+		imap[i] = 0
+	}
+
+	// fill with deduplicated columns
+	usecolumns = nil
+
+	for k := range imap {
+		usecolumns = append(usecolumns, k)
+	}
+
+	sort.Ints(usecolumns)
+
+	return usecolumns, nil
+}
+
 // prepare headers: add numbers to headers
-func numberizeAndReduceHeaders(c cfg.Config, data *Tabdata) {
+func numberizeAndReduceHeaders(conf cfg.Config, data *Tabdata) {
 	numberedHeaders := []string{}
 	maxwidth := 0 // start from scratch, so we only look at displayed column widths
 
-	for i, head := range data.headers {
-		headlen := 0
-		if len(c.Columns) > 0 {
+	for idx, head := range data.headers {
+		var headlen int
+
+		if len(conf.Columns) > 0 {
 			// -c specified
-			if !contains(c.UseColumns, i+1) {
+			if !contains(conf.UseColumns, idx+1) {
 				// ignore this one
 				continue
 			}
 		}
-		if c.NoNumbering {
+
+		if conf.NoNumbering {
 			numberedHeaders = append(numberedHeaders, head)
 			headlen = len(head)
 		} else {
-			numhead := fmt.Sprintf("%s(%d)", head, i+1)
+			numhead := fmt.Sprintf("%s(%d)", head, idx+1)
 			headlen = len(numhead)
 			numberedHeaders = append(numberedHeaders, numhead)
 		}
@@ -117,44 +213,54 @@ func numberizeAndReduceHeaders(c cfg.Config, data *Tabdata) {
 			maxwidth = headlen
 		}
 	}
+
 	data.headers = numberedHeaders
+
 	if data.maxwidthHeader != maxwidth && maxwidth > 0 {
 		data.maxwidthHeader = maxwidth
 	}
 }
 
 // exclude columns, if any
-func reduceColumns(c cfg.Config, data *Tabdata) {
-	if len(c.Columns) > 0 {
+func reduceColumns(conf cfg.Config, data *Tabdata) {
+	if len(conf.Columns) > 0 {
 		reducedEntries := [][]string{}
+
 		var reducedEntry []string
+
 		for _, entry := range data.entries {
 			reducedEntry = nil
+
 			for i, value := range entry {
-				if !contains(c.UseColumns, i+1) {
+				if !contains(conf.UseColumns, i+1) {
 					continue
 				}
 
 				reducedEntry = append(reducedEntry, value)
 			}
+
 			reducedEntries = append(reducedEntries, reducedEntry)
 		}
+
 		data.entries = reducedEntries
 	}
 }
 
+// FIXME: remove this when we only use Tablewriter and strip in ParseFile()!
 func trimRow(row []string) []string {
-	// FIXME: remove this when we only use Tablewriter and strip in ParseFile()!
-	var fixedrow []string
-	for _, cell := range row {
-		fixedrow = append(fixedrow, strings.TrimSpace(cell))
+	var fixedrow = make([]string, len(row))
+
+	for idx, cell := range row {
+		fixedrow[idx] = strings.TrimSpace(cell)
 	}
 
 	return fixedrow
 }
 
-func colorizeData(c cfg.Config, output string) string {
-	if c.UseHighlight && color.IsConsole(os.Stdout) {
+// FIXME: refactor this beast!
+func colorizeData(conf cfg.Config, output string) string {
+	switch {
+	case conf.UseHighlight && color.IsConsole(os.Stdout):
 		highlight := true
 		colorized := ""
 		first := true
@@ -167,30 +273,42 @@ func colorizeData(c cfg.Config, output string) string {
 					//  in pprint mode. This doesn't matter as long as
 					//  we don't use colorization. But with colors the
 					// missing spaces can be seen.
-					if c.OutputMode == cfg.Ascii {
-						line = line + "  "
+					if conf.OutputMode == cfg.ASCII {
+						line += "  "
 					}
 
-					line = c.HighlightHdrStyle.Sprint(line)
+					line = conf.HighlightHdrStyle.Sprint(line)
 					first = false
 				} else {
-					line = c.HighlightStyle.Sprint(line)
+					line = conf.HighlightStyle.Sprint(line)
 				}
 			} else {
-				line = c.NoHighlightStyle.Sprint(line)
+				line = conf.NoHighlightStyle.Sprint(line)
 			}
+
 			highlight = !highlight
 
 			colorized += line + "\n"
 		}
 
 		return colorized
-	} else if len(c.Pattern) > 0 && !c.NoColor && color.IsConsole(os.Stdout) {
-		r := regexp.MustCompile("(" + c.Pattern + ")")
-		return r.ReplaceAllStringFunc(output, func(in string) string {
-			return c.ColorStyle.Sprint(in)
-		})
-	} else {
+
+	case len(conf.Patterns) > 0 && !conf.NoColor && color.IsConsole(os.Stdout):
+		out := output
+
+		for _, re := range conf.Patterns {
+			if !re.Negate {
+				r := regexp.MustCompile("(" + re.Pattern + ")")
+
+				out = r.ReplaceAllStringFunc(out, func(in string) string {
+					return conf.ColorStyle.Sprint(in)
+				})
+			}
+		}
+
+		return out
+
+	default:
 		return output
 	}
 }

lib/helpers_test.go

@@ -19,9 +19,10 @@ package lib
 
 import (
 	"fmt"
-	"github.com/tlinden/tablizer/cfg"
 	"reflect"
 	"testing"
+
+	"github.com/tlinden/tablizer/cfg"
 )
 
 func TestContains(t *testing.T) {
@@ -66,23 +67,103 @@ func TestPrepareColumns(t *testing.T) {
 	}{
 		{"1,2,3", []int{1, 2, 3}, false},
 		{"1,2,", []int{}, true},
-		{"T", []int{2, 3}, false},
-		{"T,2,3", []int{2, 3}, false},
+		{"T.", []int{2, 3}, false},
+		{"T.,2,3", []int{2, 3}, false},
 		{"[a-z,4,5", []int{4, 5}, true}, // invalid regexp
 	}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("PrepareColumns-%s-%t", tt.input, tt.wanterror)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("PrepareColumns-%s-%t", testdata.input, testdata.wanterror)
 		t.Run(testname, func(t *testing.T) {
-			c := cfg.Config{Columns: tt.input}
-			err := PrepareColumns(&c, &data)
+			conf := cfg.Config{Columns: testdata.input}
+			err := PrepareColumns(&conf, &data)
 			if err != nil {
-				if !tt.wanterror {
+				if !testdata.wanterror {
 					t.Errorf("got error: %v", err)
 				}
 			} else {
-				if !reflect.DeepEqual(c.UseColumns, tt.exp) {
-					t.Errorf("got: %v, expected: %v", c.UseColumns, tt.exp)
+				if !reflect.DeepEqual(conf.UseColumns, testdata.exp) {
+					t.Errorf("got: %v, expected: %v", conf.UseColumns, testdata.exp)
+				}
+			}
+		})
+	}
+}
+
+func TestPrepareTransposerColumns(t *testing.T) {
+	data := Tabdata{
+		maxwidthHeader: 5,
+		columns:        3,
+		headers: []string{
+			"ONE", "TWO", "THREE",
+		},
+		entries: [][]string{
+			{
+				"2", "3", "4",
+			},
+		},
+	}
+
+	var tests = []struct {
+		input     string
+		transp    []string
+		exp       int
+		wanterror bool // expect error
+	}{
+		{
+			"1",
+			[]string{`/\d/x/`},
+			1,
+			false,
+		},
+		{
+			"T.", // will match [T]WO and [T]HREE
+			[]string{`/\d/x/`, `/.//`},
+			2,
+			false,
+		},
+		{
+			"TH.,2",
+			[]string{`/\d/x/`, `/.//`},
+			2,
+			false,
+		},
+		{
+			"1",
+			[]string{},
+			1,
+			true,
+		},
+		{
+			"",
+			[]string{`|.|N|`},
+			0,
+			true,
+		},
+		{
+			"1",
+			[]string{`|.|N|`},
+			1,
+			false,
+		},
+	}
+
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("PrepareTransposerColumns-%s-%t", testdata.input, testdata.wanterror)
+		t.Run(testname, func(t *testing.T) {
+			conf := cfg.Config{TransposeColumns: testdata.input, Transposers: testdata.transp}
+			err := PrepareTransposerColumns(&conf, &data)
+			if err != nil {
+				if !testdata.wanterror {
+					t.Errorf("got error: %v", err)
+				}
+			} else {
+				if len(conf.UseTransposeColumns) != testdata.exp {
+					t.Errorf("got %d, want %d", conf.UseTransposeColumns, testdata.exp)
+				}
+
+				if len(conf.Transposers) != len(conf.UseTransposeColumns) {
+					t.Errorf("got %d, want %d", conf.UseTransposeColumns, testdata.exp)
 				}
 			}
 		})
@@ -114,14 +195,16 @@ func TestReduceColumns(t *testing.T) {
 
 	input := [][]string{{"a", "b", "c"}}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("reduce-columns-by-%+v", tt.columns)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("reduce-columns-by-%+v", testdata.columns)
+
 		t.Run(testname, func(t *testing.T) {
-			c := cfg.Config{Columns: "x", UseColumns: tt.columns}
+			c := cfg.Config{Columns: "x", UseColumns: testdata.columns}
 			data := Tabdata{entries: input}
 			reduceColumns(c, &data)
-			if !reflect.DeepEqual(data.entries, tt.expect) {
-				t.Errorf("reduceColumns returned invalid data:\ngot: %+v\nexp: %+v", data.entries, tt.expect)
+			if !reflect.DeepEqual(data.entries, testdata.expect) {
+				t.Errorf("reduceColumns returned invalid data:\ngot: %+v\nexp: %+v",
+					data.entries, testdata.expect)
 			}
 		})
 	}
@@ -142,15 +225,17 @@ func TestNumberizeHeaders(t *testing.T) {
 		{[]string{"ONE", "TWO"}, []int{1, 2}, true},
 	}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("numberize-headers-columns-%+v-nonum-%t", tt.columns, tt.nonum)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("numberize-headers-columns-%+v-nonum-%t",
+			testdata.columns, testdata.nonum)
+
 		t.Run(testname, func(t *testing.T) {
-			c := cfg.Config{Columns: "x", UseColumns: tt.columns, NoNumbering: tt.nonum}
+			conf := cfg.Config{Columns: "x", UseColumns: testdata.columns, NoNumbering: testdata.nonum}
 			usedata := data
-			numberizeAndReduceHeaders(c, &usedata)
-			if !reflect.DeepEqual(usedata.headers, tt.expect) {
+			numberizeAndReduceHeaders(conf, &usedata)
+			if !reflect.DeepEqual(usedata.headers, testdata.expect) {
 				t.Errorf("numberizeAndReduceHeaders returned invalid data:\ngot: %+v\nexp: %+v",
-					usedata.headers, tt.expect)
+					usedata.headers, testdata.expect)
 			}
 		})
 	}

lib/io.go

@@ -19,91 +19,89 @@ package lib
 
 import (
 	"errors"
-	"github.com/tlinden/tablizer/cfg"
+	"fmt"
 	"io"
 	"os"
+
+	"github.com/tlinden/tablizer/cfg"
 )
 
-func ProcessFiles(c *cfg.Config, args []string) error {
-	fds, pattern, err := determineIO(c, args)
+const RWRR = 0755
+
+func ProcessFiles(conf *cfg.Config, args []string) error {
+	fd, patterns, err := determineIO(conf, args)
 
 	if err != nil {
 		return err
 	}
 
-	if err := c.PreparePattern(pattern); err != nil {
+	if err := conf.PreparePattern(patterns); err != nil {
 		return err
 	}
 
-	for _, fd := range fds {
-		data, err := Parse(*c, fd)
-		if err != nil {
-			return err
-		}
-
-		err = PrepareColumns(c, &data)
-		if err != nil {
-			return err
-		}
-
-		printData(os.Stdout, *c, &data)
+	data, err := Parse(*conf, fd)
+	if err != nil {
+		return err
 	}
 
+	if err = ValidateConsistency(&data); err != nil {
+		return err
+	}
+
+	err = PrepareSortColumns(conf, &data)
+	if err != nil {
+		return err
+	}
+
+	err = PrepareColumns(conf, &data)
+	if err != nil {
+		return err
+	}
+
+	printData(os.Stdout, *conf, &data)
+
 	return nil
 }
 
-func determineIO(c *cfg.Config, args []string) ([]io.Reader, string, error) {
-	var pattern string
-	var fds []io.Reader
+func determineIO(conf *cfg.Config, args []string) (io.Reader, []*cfg.Pattern, error) {
+	var filehandle io.Reader
+	var patterns []*cfg.Pattern
 	var haveio bool
 
-	stat, _ := os.Stdin.Stat()
-	if (stat.Mode() & os.ModeCharDevice) == 0 {
-		// we're reading from STDIN, which takes precedence over file args
-		fds = append(fds, os.Stdin)
-		if len(args) > 0 {
-			// ignore any args > 1
-			pattern = args[0]
-			c.Pattern = args[0] // used for colorization by printData()
-		}
+	switch {
+	case conf.InputFile == "-":
+		filehandle = os.Stdin
 		haveio = true
-	} else {
-		if len(args) > 0 {
-			// threre were args left, take a look
-			if args[0] == "-" {
-				// in traditional unix programs a dash denotes STDIN (forced)
-				fds = append(fds, os.Stdin)
-				haveio = true
-			} else {
-				if _, err := os.Stat(args[0]); err != nil {
-					// first  one is  not a  file, consider  it as  regexp and
-					// shift arg list
-					pattern = args[0]
-					c.Pattern = args[0] // used for colorization by printData()
-					args = args[1:]
-				}
+	case conf.InputFile != "":
+		fd, err := os.OpenFile(conf.InputFile, os.O_RDONLY, RWRR)
 
-				if len(args) > 0 {
-					// consider any other args as files
-					for _, file := range args {
+		if err != nil {
+			return nil, nil, fmt.Errorf("failed to read input file %s: %w", conf.InputFile, err)
+		}
 
-						fd, err := os.OpenFile(file, os.O_RDONLY, 0755)
+		filehandle = fd
+		haveio = true
+	}
 
-						if err != nil {
-							return nil, "", err
-						}
+	if !haveio {
+		stat, _ := os.Stdin.Stat()
+		if (stat.Mode() & os.ModeCharDevice) == 0 {
+			// we're reading from STDIN, which takes precedence over file args
+			filehandle = os.Stdin
+			haveio = true
+		}
+	}
 
-						fds = append(fds, fd)
-						haveio = true
-					}
-				}
-			}
+	if len(args) > 0 {
+		patterns = make([]*cfg.Pattern, len(args))
+		for i, arg := range args {
+			patterns[i] = &cfg.Pattern{Pattern: arg}
 		}
 	}
 
 	if !haveio {
-		return nil, "", errors.New("No file specified and nothing to read on stdin!")
+		return nil, nil, errors.New("no file specified and nothing to read on stdin")
 	}
 
-	return fds, pattern, nil
+	return filehandle, patterns, nil
 }

lib/lisp.go

@@ -1,293 +0,0 @@
-/*
-Copyright © 2023 Thomas von Dein
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-package lib
-
-import (
-	"errors"
-	"fmt"
-	"log"
-	"os"
-	"strings"
-
-	"github.com/glycerine/zygomys/zygo"
-	"github.com/tlinden/tablizer/cfg"
-)
-
-/*
-needs to be global because we can't feed an cfg object to AddHook()
-which is being called from user lisp code
-*/
-var Hooks map[string][]*zygo.SexpSymbol
-
-/*
-AddHook() (called addhook from lisp code)  can be used by the user to
-add a function to one of the available hooks provided by tablizer.
-*/
-func AddHook(env *zygo.Zlisp, name string, args []zygo.Sexp) (zygo.Sexp, error) {
-	var hookname string
-
-	if len(args) < 2 {
-		return zygo.SexpNull, errors.New("argument of %add-hook should be: %hook-name %your-function")
-	}
-
-	switch t := args[0].(type) {
-	case *zygo.SexpSymbol:
-		if !HookExists(t.Name()) {
-			return zygo.SexpNull, errors.New("Unknown hook " + t.Name())
-		}
-		hookname = t.Name()
-	default:
-		return zygo.SexpNull, errors.New("hook name must be a symbol!")
-	}
-
-	switch t := args[1].(type) {
-	case *zygo.SexpSymbol:
-		_, exists := Hooks[hookname]
-		if !exists {
-			Hooks[hookname] = []*zygo.SexpSymbol{t}
-		} else {
-			Hooks[hookname] = append(Hooks[hookname], t)
-		}
-	default:
-		return zygo.SexpNull, errors.New("hook function must be a symbol!")
-	}
-
-	return zygo.SexpNull, nil
-}
-
-/*
-Check if a hook exists
-*/
-func HookExists(key string) bool {
-	for _, hook := range cfg.ValidHooks {
-		if hook == key {
-			return true
-		}
-	}
-
-	return false
-}
-
-/*
- * Basic sanity checks and load lisp file
- */
-func LoadFile(env *zygo.Zlisp, path string) error {
-	if strings.HasSuffix(path, `.zy`) {
-		code, err := os.ReadFile(path)
-		if err != nil {
-			return err
-		}
-
-		// FIXME: check what res (_ here) could be and mean
-		_, err = env.EvalString(string(code))
-		if err != nil {
-			log.Fatalf(env.GetStackTrace(err))
-		}
-	}
-
-	return nil
-}
-
-/*
- * Setup lisp interpreter environment
- */
-func SetupLisp(c *cfg.Config) error {
-	Hooks = make(map[string][]*zygo.SexpSymbol)
-
-	env := zygo.NewZlispSandbox()
-	env.AddFunction("addhook", AddHook)
-
-	// iterate over load-path and evaluate all *.zy files there, if any
-	// we ignore if load-path does not exist, which is the default anyway
-	if path, err := os.Stat(c.LispLoadPath); !os.IsNotExist(err) {
-		if !path.IsDir() {
-			err := LoadFile(env, c.LispLoadPath)
-			if err != nil {
-				return err
-			}
-		} else {
-			dir, err := os.ReadDir(c.LispLoadPath)
-			if err != nil {
-				return err
-			}
-
-			for _, entry := range dir {
-				if !entry.IsDir() {
-					err := LoadFile(env, c.LispLoadPath+"/"+entry.Name())
-					if err != nil {
-						return err
-					}
-				}
-			}
-		}
-	}
-
-	RegisterLib(env)
-
-	c.Lisp = env
-	return nil
-}
-
-/*
-Execute every user lisp function registered as filter hook.
-
-Each function is given the current line as argument and is expected to
-return a boolean.   True indicates to keep the line,  false to skip
-it.
-
-If there  are multiple such  functions registered, then the  first one
-returning false wins,  that is if each function returns  true the line
-will  be kept,  if at  least one  of them  returns false,  it will  be
-skipped.
-*/
-func RunFilterHooks(c cfg.Config, line string) (bool, error) {
-	for _, hook := range Hooks["filter"] {
-		var result bool
-		c.Lisp.Clear()
-		res, err := c.Lisp.EvalString(fmt.Sprintf("(%s `%s`)", hook.Name(), line))
-		if err != nil {
-			return false, err
-		}
-
-		switch t := res.(type) {
-		case *zygo.SexpBool:
-			result = t.Val
-		default:
-			return false, errors.New("filter hook shall return BOOL!")
-		}
-
-		if !result {
-			// the first hook which returns false leads to complete false
-			return result, nil
-		}
-	}
-
-	// if no hook returned false, we succeed and accept the given line
-	return true, nil
-}
-
-/*
-These hooks get the data (Tabdata) readily processed by tablizer as
-argument. They are expected to  return a SexpPair containing a boolean
-denoting  if  the data  has  been  modified  and the  actual  modified
-data. Columns must  be the same, rows may differ.  Cells may also have
-been modified.
-
-Replaces the  internal data structure  Tabdata with the  user supplied
-version.
-
-Only one process hook function is supported.
-
-The somewhat complicated code is being  caused by the fact, that we
-need to convert our internal structure  to a lisp variable and vice
-versa afterwards.
-*/
-func RunProcessHooks(c cfg.Config, data Tabdata) (Tabdata, bool, error) {
-	var userdata Tabdata
-	lisplist := []zygo.Sexp{}
-
-	if len(Hooks["process"]) == 0 {
-		return userdata, false, nil
-	}
-
-	if len(Hooks["process"]) > 1 {
-		fmt.Println("Warning: only one process hook is allowed!")
-	}
-
-	// there are hook[s] installed, convert the go data structure 'data to lisp
-	for _, row := range data.entries {
-		var entry zygo.SexpHash
-
-		for idx, cell := range row {
-			err := entry.HashSet(&zygo.SexpStr{S: data.headers[idx]}, &zygo.SexpStr{S: cell})
-			if err != nil {
-				return userdata, false, err
-			}
-		}
-
-		lisplist = append(lisplist, &entry)
-	}
-
-	// we need to add it to the env so that the function can use the struct directly
-	c.Lisp.AddGlobal("data", &zygo.SexpArray{Val: lisplist, Env: c.Lisp})
-
-	// execute the actual hook
-	hook := Hooks["process"][0]
-	var result bool
-	c.Lisp.Clear()
-
-	res, err := c.Lisp.EvalString(fmt.Sprintf("(%s data)", hook.Name()))
-	if err != nil {
-		return userdata, false, err
-	}
-
-	// we expect (bool, array(hash)) as return from the function
-	switch t := res.(type) {
-	case *zygo.SexpPair:
-		switch th := t.Head.(type) {
-		case *zygo.SexpBool:
-			result = th.Val
-		default:
-			return userdata, false, errors.New("Expect (bool, array(hash)) as return value!")
-		}
-
-		switch tt := t.Tail.(type) {
-		case *zygo.SexpArray:
-			lisplist = tt.Val
-		default:
-			return userdata, false, errors.New("Expect (bool, array(hash)) as return value!")
-		}
-	default:
-		return userdata, false, errors.New("filter hook shall return array of hashes!")
-	}
-
-	if !result {
-		// no further processing required
-		return userdata, result, nil
-	}
-
-	// finally convert lispdata back to Tabdata
-	for _, item := range lisplist {
-		row := []string{}
-
-		switch hash := item.(type) {
-		case *zygo.SexpHash:
-			for _, header := range data.headers {
-				entry, err := hash.HashGetDefault(c.Lisp, &zygo.SexpStr{S: header}, &zygo.SexpStr{S: ""})
-				if err != nil {
-					return userdata, false, err
-				}
-
-				switch t := entry.(type) {
-				case *zygo.SexpStr:
-					row = append(row, t.S)
-				default:
-					return userdata, false, errors.New("Hash values should be string!")
-				}
-			}
-		default:
-			return userdata, false, errors.New("Returned array should contain hashes!")
-		}
-
-		userdata.entries = append(userdata.entries, row)
-	}
-
-	userdata.headers = data.headers
-
-	return userdata, result, nil
-}

lib/lisplib.go

@@ -1,84 +0,0 @@
-/*
-Copyright © 2023 Thomas von Dein
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-package lib
-
-import (
-	"errors"
-	"regexp"
-	"strconv"
-
-	"github.com/glycerine/zygomys/zygo"
-)
-
-func Splice2SexpList(list []string) zygo.Sexp {
-	slist := []zygo.Sexp{}
-
-	for _, item := range list {
-		slist = append(slist, &zygo.SexpStr{S: item})
-	}
-	return zygo.MakeList(slist)
-}
-
-func StringReSplit(env *zygo.Zlisp, name string, args []zygo.Sexp) (zygo.Sexp, error) {
-	if len(args) < 2 {
-		return zygo.SexpNull, errors.New("expecting 2 arguments!")
-	}
-
-	var separator string
-	var input string
-
-	switch t := args[0].(type) {
-	case *zygo.SexpStr:
-		input = t.S
-	default:
-		return zygo.SexpNull, errors.New("second argument must be a string!")
-	}
-
-	switch t := args[1].(type) {
-	case *zygo.SexpStr:
-		separator = t.S
-	default:
-		return zygo.SexpNull, errors.New("first argument must be a string!")
-	}
-
-	sep := regexp.MustCompile(separator)
-
-	return Splice2SexpList(sep.Split(input, -1)), nil
-}
-
-func String2Int(env *zygo.Zlisp, name string, args []zygo.Sexp) (zygo.Sexp, error) {
-	var number int
-
-	switch t := args[0].(type) {
-	case *zygo.SexpStr:
-		num, err := strconv.Atoi(t.S)
-		if err != nil {
-			return zygo.SexpNull, err
-		}
-		number = num
-	default:
-		return zygo.SexpNull, errors.New("argument must be a string!")
-	}
-
-	return &zygo.SexpInt{Val: int64(number)}, nil
-}
-
-func RegisterLib(env *zygo.Zlisp) {
-	env.AddFunction("resplit", StringReSplit)
-	env.AddFunction("atoi", String2Int)
-}

lib/parser.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2022 Thomas von Dein
+Copyright © 2022-2024 Thomas von Dein
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -20,91 +20,64 @@ package lib
 import (
 	"bufio"
 	"encoding/csv"
-	"errors"
 	"fmt"
 	"io"
 	"regexp"
 	"strings"
 
 	"github.com/alecthomas/repr"
-	"github.com/lithammer/fuzzysearch/fuzzy"
 	"github.com/tlinden/tablizer/cfg"
 )
 
-/*
- * [!]Match a  line, use fuzzy  search for normal pattern  strings and
- * regexp otherwise.
- */
-func matchPattern(c cfg.Config, line string) bool {
-	if len(c.Pattern) > 0 {
-		if c.UseFuzzySearch {
-			return fuzzy.MatchFold(c.Pattern, line)
-		} else {
-			return c.PatternR.MatchString(line)
-		}
-	}
-
-	return true
-}
-
 /*
 Parser switch
 */
-func Parse(c cfg.Config, input io.Reader) (Tabdata, error) {
-	if len(c.Separator) == 1 {
-		return parseCSV(c, input)
+func Parse(conf cfg.Config, input io.Reader) (Tabdata, error) {
+	var data Tabdata
+	var err error
+
+	// first step, parse the data
+	if len(conf.Separator) == 1 {
+		data, err = parseCSV(conf, input)
+	} else {
+		data, err = parseTabular(conf, input)
 	}
 
-	return parseTabular(c, input)
+	if err != nil {
+		return data, err
+	}
+
+	// 2nd step, apply filters, code or transposers, if any
+	postdata, changed, err := PostProcess(conf, &data)
+	if err != nil {
+		return data, err
+	}
+
+	if changed {
+		return *postdata, nil
+	}
+
+	return data, err
 }
 
 /*
 Parse CSV input.
 */
-func parseCSV(c cfg.Config, input io.Reader) (Tabdata, error) {
-	var content io.Reader = input
+func parseCSV(conf cfg.Config, input io.Reader) (Tabdata, error) {
 	data := Tabdata{}
 
-	if len(c.Pattern) > 0 {
-		scanner := bufio.NewScanner(input)
-		lines := []string{}
-		hadFirst := false
-		for scanner.Scan() {
-			line := strings.TrimSpace(scanner.Text())
-			if hadFirst {
-				// don't match 1st line, it's the header
-				if matchPattern(c, line) == c.InvertMatch {
-					// by default  -v is false, so if a  line does NOT
-					// match the pattern, we will ignore it. However,
-					// if the user specified -v, the matching is inverted,
-					// so we ignore all lines, which DO match.
-					continue
-				}
-
-				// apply user defined lisp filters, if any
-				accept, err := RunFilterHooks(c, line)
-				if err != nil {
-					return data, errors.Unwrap(fmt.Errorf("Failed to apply filter hook: %w", err))
-				}
-
-				if !accept {
-					//  IF there  are filter  hook[s] and  IF one  of them
-					// returns false on the current line, reject it
-					continue
-				}
-			}
-			lines = append(lines, line)
-			hadFirst = true
-		}
-		content = strings.NewReader(strings.Join(lines, "\n"))
+	// apply pattern, if any
+	content, err := FilterByPattern(conf, input)
+	if err != nil {
+		return data, err
 	}
 
 	csvreader := csv.NewReader(content)
-	csvreader.Comma = rune(c.Separator[0])
+	csvreader.Comma = rune(conf.Separator[0])
 
 	records, err := csvreader.ReadAll()
 	if err != nil {
-		return data, errors.Unwrap(fmt.Errorf("Could not parse CSV input: %w", err))
+		return data, fmt.Errorf("could not parse CSV input: %w", err)
 	}
 
 	if len(records) >= 1 {
@@ -124,28 +97,19 @@ func parseCSV(c cfg.Config, input io.Reader) (Tabdata, error) {
 		}
 	}
 
-	// apply user defined lisp process hooks, if any
-	userdata, changed, err := RunProcessHooks(c, data)
-	if err != nil {
-		return data, errors.Unwrap(fmt.Errorf("Failed to apply filter hook: %w", err))
-	}
-	if changed {
-		data = userdata
-	}
-
 	return data, nil
 }
 
 /*
 Parse tabular input.
 */
-func parseTabular(c cfg.Config, input io.Reader) (Tabdata, error) {
+func parseTabular(conf cfg.Config, input io.Reader) (Tabdata, error) {
 	data := Tabdata{}
 
 	var scanner *bufio.Scanner
 
 	hadFirst := false
-	separate := regexp.MustCompile(c.Separator)
+	separate := regexp.MustCompile(conf.Separator)
 
 	scanner = bufio.NewScanner(input)
 
@@ -156,16 +120,9 @@ func parseTabular(c cfg.Config, input io.Reader) (Tabdata, error) {
 		if !hadFirst {
 			// header processing
 			data.columns = len(parts)
-			// if Debug {
-			// 	fmt.Println(parts)
-			// }
 
 			// process all header fields
 			for _, part := range parts {
-				// if Debug {
-				// 	fmt.Printf("Part: <%s>\n", string(line[beg:part[0]]))
-				//}
-
 				// register widest header field
 				headerlen := len(part)
 				if headerlen > data.maxwidthHeader {
@@ -180,7 +137,7 @@ func parseTabular(c cfg.Config, input io.Reader) (Tabdata, error) {
 			}
 		} else {
 			// data processing
-			if matchPattern(c, line) == c.InvertMatch {
+			if matchPattern(conf, line) == conf.InvertMatch {
 				// by default  -v is false, so if a  line does NOT
 				// match the pattern, we will ignore it. However,
 				// if the user specified -v, the matching is inverted,
@@ -188,18 +145,6 @@ func parseTabular(c cfg.Config, input io.Reader) (Tabdata, error) {
 				continue
 			}
 
-			// apply user defined lisp filters, if any
-			accept, err := RunFilterHooks(c, line)
-			if err != nil {
-				return data, errors.Unwrap(fmt.Errorf("Failed to apply filter hook: %w", err))
-			}
-
-			if !accept {
-				//  IF there  are filter  hook[s] and  IF one  of them
-				// returns false on the current line, reject it
-				continue
-			}
-
 			idx := 0 // we cannot use the header index, because we could exclude columns
 			values := []string{}
 			for _, part := range parts {
@@ -221,21 +166,45 @@ func parseTabular(c cfg.Config, input io.Reader) (Tabdata, error) {
 	}
 
 	if scanner.Err() != nil {
-		return data, errors.Unwrap(fmt.Errorf("Failed to read from io.Reader: %w", scanner.Err()))
-	}
-
-	// apply user defined lisp process hooks, if any
-	userdata, changed, err := RunProcessHooks(c, data)
-	if err != nil {
-		return data, errors.Unwrap(fmt.Errorf("Failed to apply filter hook: %w", err))
-	}
-	if changed {
-		data = userdata
-	}
-
-	if c.Debug {
-		repr.Print(data)
+		return data, fmt.Errorf("failed to read from io.Reader: %w", scanner.Err())
 	}
 
 	return data, nil
 }
+
+func PostProcess(conf cfg.Config, data *Tabdata) (*Tabdata, bool, error) {
+	var modified bool
+
+	// filter by field filters, if any
+	filtereddata, changed, err := FilterByFields(conf, data)
+	if err != nil {
+		return data, false, fmt.Errorf("failed to filter fields: %w", err)
+	}
+
+	if changed {
+		data = filtereddata
+		modified = true
+	}
+
+	// check if transposers are valid and turn into Transposer structs
+	if err := PrepareTransposerColumns(&conf, data); err != nil {
+		return data, false, err
+	}
+
+	// transpose if demanded
+	modifieddata, changed, err := TransposeFields(conf, data)
+	if err != nil {
+		return data, false, fmt.Errorf("failed to transpose fields: %w", err)
+	}
+
+	if changed {
+		data = modifieddata
+		modified = true
+	}
+
+	if conf.Debug {
+		repr.Print(data)
+	}
+
+	return data, modified, nil
+}

lib/parser_test.go

@@ -62,12 +62,12 @@ func TestParser(t *testing.T) {
 		},
 	}
 
-	for _, in := range input {
-		testname := fmt.Sprintf("parse-%s", in.name)
+	for _, testdata := range input {
+		testname := fmt.Sprintf("parse-%s", testdata.name)
 		t.Run(testname, func(t *testing.T) {
-			readFd := strings.NewReader(strings.TrimSpace(in.text))
-			c := cfg.Config{Separator: in.separator}
-			gotdata, err := Parse(c, readFd)
+			readFd := strings.NewReader(strings.TrimSpace(testdata.text))
+			conf := cfg.Config{Separator: testdata.separator}
+			gotdata, err := Parse(conf, readFd)
 
 			if err != nil {
 				t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)
@@ -83,49 +83,55 @@ func TestParser(t *testing.T) {
 
 func TestParserPatternmatching(t *testing.T) {
 	var tests = []struct {
-		entries [][]string
-		pattern string
-		invert  bool
-		want    bool
+		name     string
+		entries  [][]string
+		patterns []*cfg.Pattern
+		invert   bool
+		want     bool
 	}{
 		{
+			name: "match",
 			entries: [][]string{
 				{"asd", "igig", "cxxxncnc"},
 			},
-			pattern: "ig",
-			invert:  false,
+			patterns: []*cfg.Pattern{{Pattern: "ig"}},
+			invert:   false,
 		},
 		{
+			name: "invert",
 			entries: [][]string{
 				{"19191", "EDD 1", "X"},
 			},
-			pattern: "ig",
-			invert:  true,
+			patterns: []*cfg.Pattern{{Pattern: "ig"}},
+			invert:   true,
 		},
 	}
 
-	for _, in := range input {
-		for _, tt := range tests {
+	for _, inputdata := range input {
+		for _, testdata := range tests {
 			testname := fmt.Sprintf("parse-%s-with-pattern-%s-inverted-%t",
-				in.name, tt.pattern, tt.invert)
+				inputdata.name, testdata.name, testdata.invert)
 			t.Run(testname, func(t *testing.T) {
-				c := cfg.Config{InvertMatch: tt.invert, Pattern: tt.pattern,
-					Separator: in.separator}
+				conf := cfg.Config{
+					InvertMatch: testdata.invert,
+					Patterns:    testdata.patterns,
+					Separator:   inputdata.separator,
+				}
 
-				_ = c.PreparePattern(tt.pattern)
+				_ = conf.PreparePattern(testdata.patterns)
 
-				readFd := strings.NewReader(strings.TrimSpace(in.text))
-				gotdata, err := Parse(c, readFd)
+				readFd := strings.NewReader(strings.TrimSpace(inputdata.text))
+				gotdata, err := Parse(conf, readFd)
 
 				if err != nil {
-					if !tt.want {
+					if !testdata.want {
 						t.Errorf("Parser returned error: %s\nData processed so far: %+v",
 							err, gotdata)
 					}
 				} else {
-					if !reflect.DeepEqual(tt.entries, gotdata.entries) {
+					if !reflect.DeepEqual(testdata.entries, gotdata.entries) {
 						t.Errorf("Parser returned invalid data (pattern: %s, invert: %t)\nExp: %+v\nGot: %+v\n",
-							tt.pattern, tt.invert, tt.entries, gotdata.entries)
+							testdata.name, testdata.invert, testdata.entries, gotdata.entries)
 					}
 				}
 			})
@@ -152,8 +158,8 @@ asd    igig
 19191  EDD 1  X`
 
 	readFd := strings.NewReader(strings.TrimSpace(table))
-	c := cfg.Config{Separator: cfg.DefaultSeparator}
-	gotdata, err := Parse(c, readFd)
+	conf := cfg.Config{Separator: cfg.DefaultSeparator}
+	gotdata, err := Parse(conf, readFd)
 
 	if err != nil {
 		t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)
@@ -161,6 +167,6 @@ asd    igig
 
 	if !reflect.DeepEqual(data, gotdata) {
 		t.Errorf("Parser returned invalid data, Regex: %s\nExp: %+v\nGot: %+v\n",
-			c.Separator, data, gotdata)
+			conf.Separator, data, gotdata)
 	}
 }

lib/printer.go

@@ -32,51 +32,50 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-func printData(w io.Writer, c cfg.Config, data *Tabdata) {
-	// some output preparations:
+func printData(writer io.Writer, conf cfg.Config, data *Tabdata) {
+	//  Sort   the  data  first,  before   headers+entries  are  being
+	// reduced. That way the user can specify any valid column to sort
+	// by, independently if it's being used for display or not.
+	sortTable(conf, data)
 
-	// add numbers to headers and remove this we're not interested in
-	numberizeAndReduceHeaders(c, data)
+	// add numbers to headers and remove those we're not interested in
+	numberizeAndReduceHeaders(conf, data)
 
 	// remove unwanted columns, if any
-	reduceColumns(c, data)
+	reduceColumns(conf, data)
 
-	// sort the data
-	sortTable(c, data)
-
-	switch c.OutputMode {
+	switch conf.OutputMode {
 	case cfg.Extended:
-		printExtendedData(w, c, data)
-	case cfg.Ascii:
-		printAsciiData(w, c, data)
+		printExtendedData(writer, conf, data)
+	case cfg.ASCII:
+		printASCIIData(writer, conf, data)
 	case cfg.Orgtbl:
-		printOrgmodeData(w, c, data)
+		printOrgmodeData(writer, conf, data)
 	case cfg.Markdown:
-		printMarkdownData(w, c, data)
+		printMarkdownData(writer, conf, data)
 	case cfg.Shell:
-		printShellData(w, c, data)
+		printShellData(writer, data)
 	case cfg.Yaml:
-		printYamlData(w, c, data)
+		printYamlData(writer, data)
 	case cfg.CSV:
-		printCSVData(w, c, data)
+		printCSVData(writer, data)
 	default:
-		printAsciiData(w, c, data)
+		printASCIIData(writer, conf, data)
 	}
-
 }
 
-func output(w io.Writer, str string) {
-	fmt.Fprint(w, str)
+func output(writer io.Writer, str string) {
+	fmt.Fprint(writer, str)
 }
 
 /*
 Emacs org-mode compatible table (also orgtbl-mode)
 */
-func printOrgmodeData(w io.Writer, c cfg.Config, data *Tabdata) {
+func printOrgmodeData(writer io.Writer, conf cfg.Config, data *Tabdata) {
 	tableString := &strings.Builder{}
 	table := tablewriter.NewWriter(tableString)
 
-	if !c.NoHeaders {
+	if !conf.NoHeaders {
 		table.SetHeader(data.headers)
 	}
 
@@ -100,8 +99,8 @@ func printOrgmodeData(w io.Writer, c cfg.Config, data *Tabdata) {
 	leftR := regexp.MustCompile(`(?m)^\\+`)
 	rightR := regexp.MustCompile(`\\+(?m)$`)
 
-	output(w, color.Sprint(
-		colorizeData(c,
+	output(writer, color.Sprint(
+		colorizeData(conf,
 			rightR.ReplaceAllString(
 				leftR.ReplaceAllString(tableString.String(), "|"), "|"))))
 }
@@ -109,11 +108,11 @@ func printOrgmodeData(w io.Writer, c cfg.Config, data *Tabdata) {
 /*
 Markdown table
 */
-func printMarkdownData(w io.Writer, c cfg.Config, data *Tabdata) {
+func printMarkdownData(writer io.Writer, conf cfg.Config, data *Tabdata) {
 	tableString := &strings.Builder{}
 	table := tablewriter.NewWriter(tableString)
 
-	if !c.NoHeaders {
+	if !conf.NoHeaders {
 		table.SetHeader(data.headers)
 	}
 
@@ -125,19 +124,20 @@ func printMarkdownData(w io.Writer, c cfg.Config, data *Tabdata) {
 	table.SetCenterSeparator("|")
 
 	table.Render()
-	output(w, color.Sprint(colorizeData(c, tableString.String())))
+	output(writer, color.Sprint(colorizeData(conf, tableString.String())))
 }
 
 /*
 Simple ASCII table without any borders etc, just like the input we expect
 */
-func printAsciiData(w io.Writer, c cfg.Config, data *Tabdata) {
+func printASCIIData(writer io.Writer, conf cfg.Config, data *Tabdata) {
 	tableString := &strings.Builder{}
 	table := tablewriter.NewWriter(tableString)
 
-	if !c.NoHeaders {
+	if !conf.NoHeaders {
 		table.SetHeader(data.headers)
 	}
+
 	table.AppendBulk(data.entries)
 
 	table.SetAutoWrapText(false)
@@ -151,7 +151,7 @@ func printAsciiData(w io.Writer, c cfg.Config, data *Tabdata) {
 	table.SetBorder(false)
 	table.SetNoWhiteSpace(true)
 
-	if !c.UseHighlight {
+	if !conf.UseHighlight {
 		// the tabs destroy the highlighting
 		table.SetTablePadding("\t") // pad with tabs
 	} else {
@@ -159,16 +159,17 @@ func printAsciiData(w io.Writer, c cfg.Config, data *Tabdata) {
 	}
 
 	table.Render()
-	output(w, color.Sprint(colorizeData(c, tableString.String())))
+	output(writer, color.Sprint(colorizeData(conf, tableString.String())))
 }
 
 /*
 We simulate the \x command of psql (the PostgreSQL client)
 */
-func printExtendedData(w io.Writer, c cfg.Config, data *Tabdata) {
+func printExtendedData(writer io.Writer, conf cfg.Config, data *Tabdata) {
 	// needed for data output
 	format := fmt.Sprintf("%%%ds: %%s\n", data.maxwidthHeader)
 	out := ""
+
 	if len(data.entries) > 0 {
 		for _, entry := range data.entries {
 			for i, value := range entry {
@@ -179,67 +180,71 @@ func printExtendedData(w io.Writer, c cfg.Config, data *Tabdata) {
 		}
 	}
 
-	output(w, colorizeData(c, out))
+	output(writer, colorizeData(conf, out))
 }
 
 /*
 Shell output, ready to be eval'd. Just like FreeBSD stat(1)
 */
-func printShellData(w io.Writer, c cfg.Config, data *Tabdata) {
+func printShellData(writer io.Writer, data *Tabdata) {
 	out := ""
+
 	if len(data.entries) > 0 {
 		for _, entry := range data.entries {
 			shentries := []string{}
-			for i, value := range entry {
+
+			for idx, value := range entry {
 				shentries = append(shentries, fmt.Sprintf("%s=\"%s\"",
-					data.headers[i], value))
+					data.headers[idx], value))
 			}
-			out += fmt.Sprint(strings.Join(shentries, " ")) + "\n"
+
+			out += strings.Join(shentries, " ") + "\n"
 		}
 	}
 
 	// no colorization here
-	output(w, out)
+	output(writer, out)
 }
 
-func printYamlData(w io.Writer, c cfg.Config, data *Tabdata) {
-	type D struct {
+func printYamlData(writer io.Writer, data *Tabdata) {
+	type Data struct {
 		Entries []map[string]interface{} `yaml:"entries"`
 	}
 
-	d := D{}
+	yamlout := Data{}
 
 	for _, entry := range data.entries {
-		ml := map[string]interface{}{}
+		yamldata := map[string]interface{}{}
 
-		for i, entry := range entry {
+		for idx, entry := range entry {
 			style := yaml.TaggedStyle
+
 			_, err := strconv.Atoi(entry)
 			if err != nil {
 				style = yaml.DoubleQuotedStyle
 			}
 
-			ml[strings.ToLower(data.headers[i])] =
+			yamldata[strings.ToLower(data.headers[idx])] =
 				&yaml.Node{
 					Kind:  yaml.ScalarNode,
 					Style: style,
 					Value: entry}
 		}
 
-		d.Entries = append(d.Entries, ml)
+		yamlout.Entries = append(yamlout.Entries, yamldata)
 	}
 
-	yamlstr, err := yaml.Marshal(&d)
+	yamlstr, err := yaml.Marshal(&yamlout)
 
 	if err != nil {
 		log.Fatal(err)
 	}
 
-	output(w, string(yamlstr))
+	output(writer, string(yamlstr))
 }
 
-func printCSVData(w io.Writer, c cfg.Config, data *Tabdata) {
-	csvout := csv.NewWriter(w)
+func printCSVData(writer io.Writer, data *Tabdata) {
+	csvout := csv.NewWriter(writer)
 
 	if err := csvout.Write(data.headers); err != nil {
 		log.Fatalln("error writing record to csv:", err)

lib/printer_test.go

@@ -20,10 +20,10 @@ package lib
 import (
 	"bytes"
 	"fmt"
-	//"github.com/alecthomas/repr"
-	"github.com/tlinden/tablizer/cfg"
 	"strings"
 	"testing"
+
+	"github.com/tlinden/tablizer/cfg"
 )
 
 func newData() Tabdata {
@@ -63,7 +63,7 @@ var tests = []struct {
 	name string // so we can identify which one fails, can be the same
 	// for multiple tests, because flags will be appended to the name
 	sortby    string // empty == default
-	column    int    // sort by this column, 0 == default first or NO Sort
+	column    int    // sort by this column (numbers start by 1)
 	desc      bool   // sort in descending order, default == ascending
 	nonum     bool   // hide numbering
 	mode      int    // shell, orgtbl, etc. empty == default: ascii
@@ -73,7 +73,7 @@ var tests = []struct {
 }{
 	// --------------------- Default settings mode tests ``
 	{
-		mode: cfg.Ascii,
+		mode: cfg.ASCII,
 		name: "default",
 		expect: `
 NAME(1)	DURATION(2)	COUNT(3)	WHEN(4)                    
@@ -162,7 +162,7 @@ DURATION(2): 33d12h
 
 	//------------------------ SORT TESTS
 	{
-		name:   "sortbycolumn",
+		name:   "sortbycolumn3",
 		column: 3,
 		sortby: "numeric",
 		desc:   false,
@@ -173,7 +173,7 @@ beta   	1d10h5m1s  	33      	3/1/2014
 alpha  	4h35m      	170     	2013-Feb-03`,
 	},
 	{
-		name:   "sortbycolumn",
+		name:   "sortbycolumn4",
 		column: 4,
 		sortby: "time",
 		desc:   false,
@@ -184,7 +184,7 @@ alpha  	4h35m      	170     	2013-Feb-03
 beta   	1d10h5m1s  	33      	3/1/2014`,
 	},
 	{
-		name:   "sortbycolumn",
+		name:   "sortbycolumn2",
 		column: 2,
 		sortby: "duration",
 		desc:   false,
@@ -250,39 +250,42 @@ DURATION(2)	WHEN(4)
 }
 
 func TestPrinter(t *testing.T) {
-	for _, tt := range tests {
-		testname := fmt.Sprintf("print-sortcol-%d-desc-%t-sortby-%s-mode-%d-usecolumns-%s",
-			tt.column, tt.desc, tt.sortby, tt.mode, tt.usecolstr)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("print-%s-%d-desc-%t-sortby-%s-mode-%d-usecolumns-%s",
+			testdata.name, testdata.column, testdata.desc, testdata.sortby, testdata.mode, testdata.usecolstr)
 		t.Run(testname, func(t *testing.T) {
 			// replaces os.Stdout, but we ignore it
-			var w bytes.Buffer
+			var writer bytes.Buffer
 
 			// cmd flags
-			c := cfg.Config{
-				SortByColumn:   tt.column,
-				SortDescending: tt.desc,
-				SortMode:       tt.sortby,
-				OutputMode:     tt.mode,
-				NoNumbering:    tt.nonum,
-				UseColumns:     tt.usecol,
+			conf := cfg.Config{
+				SortDescending: testdata.desc,
+				SortMode:       testdata.sortby,
+				OutputMode:     testdata.mode,
+				NoNumbering:    testdata.nonum,
+				UseColumns:     testdata.usecol,
 				NoColor:        true,
 			}
 
-			c.ApplyDefaults()
-
-			// the test checks the len!
-			if len(tt.usecol) > 0 {
-				c.Columns = "yes"
-			} else {
-				c.Columns = ""
+			if testdata.column > 0 {
+				conf.UseSortByColumn = []int{testdata.column}
 			}
 
-			testdata := newData()
-			exp := strings.TrimSpace(tt.expect)
+			conf.ApplyDefaults()
 
-			printData(&w, c, &testdata)
+			// the test checks the len!
+			if len(testdata.usecol) > 0 {
+				conf.Columns = "yes"
+			} else {
+				conf.Columns = ""
+			}
 
-			got := strings.TrimSpace(w.String())
+			data := newData()
+			exp := strings.TrimSpace(testdata.expect)
+
+			printData(&writer, conf, &data)
+
+			got := strings.TrimSpace(writer.String())
 
 			if got != exp {
 				t.Errorf("not rendered correctly:\n+++ got:\n%s\n+++ want:\n%s",

lib/sort.go

@@ -18,84 +18,102 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package lib
 
 import (
-	"github.com/araddon/dateparse"
-	"github.com/tlinden/tablizer/cfg"
+	"cmp"
 	"regexp"
 	"sort"
 	"strconv"
+
+	"github.com/araddon/dateparse"
+	"github.com/tlinden/tablizer/cfg"
 )
 
-func sortTable(c cfg.Config, data *Tabdata) {
-	if c.SortByColumn <= 0 {
+func sortTable(conf cfg.Config, data *Tabdata) {
+	if len(conf.UseSortByColumn) == 0 {
 		// no sorting wanted
 		return
 	}
 
-	// slightly modified here to match internal array indicies
-	col := c.SortByColumn
-
-	col-- // ui starts counting by 1, but use 0 internally
-
 	// sanity checks
 	if len(data.entries) == 0 {
 		return
 	}
 
-	if col >= len(data.headers) {
-		// fall back to default column
-		col = 0
-	}
-
 	// actual sorting
 	sort.SliceStable(data.entries, func(i, j int) bool {
-		return compare(&c, data.entries[i][col], data.entries[j][col])
+		// holds the result of a sort of one column
+		comparators := []int{}
+
+		// iterate over all columns to be sorted, conf.SortMode must be identical!
+		for _, column := range conf.UseSortByColumn {
+			comparators = append(comparators, compare(&conf, data.entries[i][column-1], data.entries[j][column-1]))
+		}
+
+		// return the combined result
+		res := cmp.Or(comparators...)
+
+		switch res {
+		case 0:
+			return true
+		default:
+			return false
+		}
+
 	})
 }
 
 // config is not modified here, but it would be inefficient to copy it every loop
-func compare(c *cfg.Config, a string, b string) bool {
+func compare(conf *cfg.Config, left string, right string) int {
 	var comp bool
 
-	switch c.SortMode {
+	switch conf.SortMode {
 	case "numeric":
-		left, err := strconv.Atoi(a)
+		left, err := strconv.Atoi(left)
 		if err != nil {
 			left = 0
 		}
-		right, err := strconv.Atoi(b)
+
+		right, err := strconv.Atoi(right)
 		if err != nil {
 			right = 0
 		}
+
 		comp = left < right
 	case "duration":
-		left := duration2int(a)
-		right := duration2int(b)
+		left := duration2int(left)
+		right := duration2int(right)
+
 		comp = left < right
 	case "time":
-		left, _ := dateparse.ParseAny(a)
-		right, _ := dateparse.ParseAny(b)
+		left, _ := dateparse.ParseAny(left)
+		right, _ := dateparse.ParseAny(right)
+
 		comp = left.Unix() < right.Unix()
 	default:
-		comp = a < b
+		comp = left < right
 	}
 
-	if c.SortDescending {
+	if conf.SortDescending {
 		comp = !comp
 	}
 
-	return comp
+	switch comp {
+	case true:
+		return 0
+	default:
+		return 1
+	}
 }
 
 /*
-   We could use time.ParseDuration(), but this doesn't support days.
+We could use time.ParseDuration(), but this doesn't support days.
 
-   We  could also  use github.com/xhit/go-str2duration/v2,  which does
-   the job,  but it's  just another dependency,  just for  this little
-   gem. And  we don't need a  time.Time value. And int  is good enough
-   for duration comparision.
+We  could also  use github.com/xhit/go-str2duration/v2,  which does
+the job,  but it's  just another dependency,  just for  this little
+gem. And  we don't need a  time.Time value. And int  is good enough
+for duration comparison.
 
-   Convert a  durartion into  an integer.  Valid  time units  are "s",
-   "m", "h" and "d".
+Convert a  duration into  an integer.  Valid  time units  are "s",
+"m", "h" and "d".
 */
 func duration2int(duration string) int {
 	re := regexp.MustCompile(`(\d+)([dhms])`)
@@ -103,16 +121,17 @@ func duration2int(duration string) int {
 
 	for _, match := range re.FindAllStringSubmatch(duration, -1) {
 		if len(match) == 3 {
-			v, _ := strconv.Atoi(match[1])
+			durationvalue, _ := strconv.Atoi(match[1])
+
 			switch match[2][0] {
 			case 'd':
-				seconds += v * 86400
+				seconds += durationvalue * 86400
 			case 'h':
-				seconds += v * 3600
+				seconds += durationvalue * 3600
 			case 'm':
-				seconds += v * 60
+				seconds += durationvalue * 60
 			case 's':
-				seconds += v
+				seconds += durationvalue
 			}
 		}
 	}

lib/sort_test.go

@@ -19,8 +19,9 @@ package lib
 
 import (
 	"fmt"
-	"github.com/tlinden/tablizer/cfg"
 	"testing"
+
+	"github.com/tlinden/tablizer/cfg"
 )
 
 func TestDuration2Seconds(t *testing.T) {
@@ -36,12 +37,12 @@ func TestDuration2Seconds(t *testing.T) {
 		{"19t77X what?4s", 4},
 	}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("duration-%s", tt.dur)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("duration-%s", testdata.dur)
 		t.Run(testname, func(t *testing.T) {
-			seconds := duration2int(tt.dur)
-			if seconds != tt.expect {
-				t.Errorf("got %d, want %d", seconds, tt.expect)
+			seconds := duration2int(testdata.dur)
+			if seconds != testdata.expect {
+				t.Errorf("got %d, want %d", seconds, testdata.expect)
 			}
 		})
 	}
@@ -52,27 +53,29 @@ func TestCompare(t *testing.T) {
 		mode string
 		a    string
 		b    string
-		want bool
+		want int
 		desc bool
 	}{
 		// ascending
-		{"numeric", "10", "20", true, false},
-		{"duration", "2d4h5m", "45m", false, false},
-		{"time", "12/24/2022", "1/1/1970", false, false},
+		{"numeric", "10", "20", 0, false},
+		{"duration", "2d4h5m", "45m", 1, false},
+		{"time", "12/24/2022", "1/1/1970", 1, false},
 
 		// descending
-		{"numeric", "10", "20", false, true},
-		{"duration", "2d4h5m", "45m", true, true},
-		{"time", "12/24/2022", "1/1/1970", true, true},
+		{"numeric", "10", "20", 1, true},
+		{"duration", "2d4h5m", "45m", 0, true},
+		{"time", "12/24/2022", "1/1/1970", 0, true},
 	}
 
-	for _, tt := range tests {
-		testname := fmt.Sprintf("compare-mode-%s-a-%s-b-%s-desc-%t", tt.mode, tt.a, tt.b, tt.desc)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("compare-mode-%s-a-%s-b-%s-desc-%t",
+			testdata.mode, testdata.a, testdata.b, testdata.desc)
+
 		t.Run(testname, func(t *testing.T) {
-			c := cfg.Config{SortMode: tt.mode, SortDescending: tt.desc}
-			got := compare(&c, tt.a, tt.b)
-			if got != tt.want {
-				t.Errorf("got %t, want %t", got, tt.want)
+			c := cfg.Config{SortMode: testdata.mode, SortDescending: testdata.desc}
+			got := compare(&c, testdata.a, testdata.b)
+			if got != testdata.want {
+				t.Errorf("got %d, want %d", got, testdata.want)
 			}
 		})
 	}

main.go

@@ -18,9 +18,17 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package main
 
 import (
+	"os"
+
 	"github.com/tlinden/tablizer/cmd"
 )
 
 func main() {
-	cmd.Execute()
+	os.Exit(Main())
+}
+
+func Main() int {
+	cmd.Execute()
+
+	return 0 // cmd takes care of exit 1 itself
 }

main_test.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"os"
+	"testing"
+
+	"github.com/rogpeppe/go-internal/testscript"
+)
+
+func TestMain(m *testing.M) {
+	os.Exit(testscript.RunMain(m, map[string]func() int{
+		"tablizer": Main,
+	}))
+}
+
+func TestTablizer(t *testing.T) {
+	testscript.Run(t, testscript.Params{
+		Dir: "t",
+	})
+}

t/test-basics.txtar

@@ -0,0 +1,43 @@
+# usage
+exec tablizer -h
+stdout Usage
+
+# version
+exec tablizer -V
+stdout version
+
+# manpage
+exec tablizer -m
+stdout SYNOPSIS
+
+# completion
+exec tablizer --completion bash
+stdout __tablizer_init_completion
+
+# use config (configures  colors, but these are not  being used, since
+# this  env doesn't  support it,  but at  least it  should succeed.
+exec tablizer -f config.hcl -r testtable.txt Runn
+stdout Runn
+
+
+
+# will be automatically created in work dir
+-- testtable.txt --
+NAME                                                 READY   STATUS    RESTARTS       AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35 (45m ago)   11d
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17 (45m ago)   1d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17 (45m ago)   1h44m
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20 (45m ago)   45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17 (45m ago)   54s
+
+
+-- config.hcl --
+BG             = "lightGreen"
+FG             = "white"
+HighlightBG    = "lightGreen"
+HighlightFG    = "white"
+NoHighlightBG  = "white"
+NoHighlightFG  = "lightGreen"
+HighlightHdrBG = "red"
+HighlightHdrFG = "white"
+

t/test-csv.txtar

@@ -0,0 +1,26 @@
+# reading from file and matching with lowercase words
+exec tablizer -c name,status -r testtable.csv -s,
+stdout grafana.*Runn
+
+# matching mixed case
+exec tablizer -c NAME,staTUS -r testtable.csv -s,
+stdout grafana.*Runn
+
+# matching using numbers
+exec tablizer -c 1,3 -r testtable.csv -s,
+stdout grafana.*Runn
+
+# matching using regex
+exec tablizer -c 'na.*,stat.' -r testtable.csv -s,
+stdout grafana.*Runn
+
+
+# will be automatically created in work dir
+-- testtable.csv --
+NAME,READY,STATUS,RESTARTS,AGE
+alertmanager-kube-prometheus-alertmanager-0,2/2,Running,35 (45m ago),11d
+grafana-fcc54cbc9-bk7s8,1/1,Running,17 (45m ago),1d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7,1/1,Running,17 (45m ago),1h44m
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f,1/1,Running,20 (45m ago),45m
+kube-prometheus-node-exporter-bfzpl,1/1,Running,17 (45m ago),54s
+

t/test-filtering.txtar

@@ -0,0 +1,21 @@
+# filtering
+exec tablizer -r testtable.txt -F name=grafana
+stdout grafana.*Runn
+
+# filtering two columns
+exec tablizer -r testtable.txt -F name=prometh -F age=1h
+stdout blackbox.*Runn
+
+# filtering two same columns
+exec tablizer -r testtable.txt -F name=prometh -F name=alert
+stdout prometheus-alertmanager.*Runn
+
+
+# will be automatically created in work dir
+-- testtable.txt --
+NAME                                                 READY   STATUS    RESTARTS       AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35 (45m ago)   11d
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17 (45m ago)   1d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17 (45m ago)   1h44m
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20 (45m ago)   45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17 (45m ago)   54s

t/test-headermatching.txtar

@@ -0,0 +1,25 @@
+# reading from file and matching with lowercase words
+exec tablizer -c name,status -r testtable.txt
+stdout grafana.*Runn
+
+# matching mixed case
+exec tablizer -c NAME,staTUS -r testtable.txt
+stdout grafana.*Runn
+
+# matching using numbers
+exec tablizer -c 1,3 -r testtable.txt
+stdout grafana.*Runn
+
+# matching using regex
+exec tablizer -c 'na.*,stat.' -r testtable.txt
+stdout grafana.*Runn
+
+
+# will be automatically created in work dir
+-- testtable.txt --
+NAME                                                 READY   STATUS    RESTARTS       AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35 (45m ago)   11d
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17 (45m ago)   1d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17 (45m ago)   1h44m
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20 (45m ago)   45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17 (45m ago)   54s

t/test-multipatterns.txtar

@@ -0,0 +1,46 @@
+# filtering
+
+# a AND b
+exec tablizer -r testtable.txt -H -cspecies invasive imperium
+stdout 'namak'
+! stdout human
+
+# a AND !b
+exec tablizer -r testtable.txt -H -cspecies invasive '/imperium/!'
+stdout 'human'
+! stdout namak
+
+# a AND !b AND c
+exec tablizer -r testtable.txt -H -cspecies peaceful '/imperium/!' planetary
+stdout 'kenaha'
+! stdout 'namak|heduu|riedl'
+
+# case insensitive
+exec tablizer -r testtable.txt -H -cspecies '/REGIONAL/i'
+stdout namak
+! stdout 'human|riedl|heduu|kenaa'
+
+# case insensitive negated
+exec tablizer -r testtable.txt -H -cspecies '/REGIONAL/!i'
+stdout 'human|riedl|heduu|kenaa'
+! stdout namak
+
+# !a AND !b
+exec tablizer -r testtable.txt -H -cspecies '/galactic/!' '/planetary/!'
+stdout namak
+! stdout 'human|riedl|heduu|kenaa'
+
+# same case insensitive
+exec tablizer -r testtable.txt -H -cspecies '/GALACTIC/i!' '/PLANETARY/!i'
+stdout namak
+! stdout 'human|riedl|heduu|kenaa'
+
+# will be automatically created in work dir
+-- testtable.txt --
+SPECIES   TYPE         HOME     STAGE             SPREAD
+human     invasive     earth    brink             planetary
+riedl     peaceful     keauna   civilized         pangalactic
+namak     invasive     namak    imperium          regional
+heduu     peaceful     iu       imperium          galactic
+kenaha    peaceful     kohi     hunter-gatherer   planetary
+

t/test-sort.txtar

@@ -0,0 +1,49 @@
+# sort by name
+exec tablizer -r testtable.txt -k 1
+stdout '^alert.*\n^grafana.*\n^kube'
+
+# sort by name reversed
+exec tablizer -r testtable.txt -k 1 -D
+stdout 'kube.*\n^grafana.*\n^alert'
+
+# sort by starts numerically
+exec tablizer -r testtable.txt -k 4 -i -c4
+stdout '17\s*\n^20\s*\n^35'
+
+# sort by starts numerically reversed
+exec tablizer -r testtable.txt -k 4 -i -c4 -D
+stdout '35\s*\n^20\s*\n^17'
+
+# sort by age
+exec tablizer -r testtable.txt -k 5 -a
+stdout '45m\s*\n.*1h44m'
+
+# sort by age reverse
+exec tablizer -r testtable.txt -k 5 -a -D
+stdout '1h44m\s*\n.*45m'
+
+# sort by time
+exec tablizer -r timetable.txt -k 2 -t
+stdout '^sel.*\n^foo.*\nbar'
+
+# sort by time reverse
+exec tablizer -r timetable.txt -k 2 -t -D
+stdout '^bar.*\n^foo.*\nsel'
+
+
+# will be automatically created in work dir
+-- testtable.txt --
+NAME                                                 READY   STATUS    STARTS      AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35          11d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17          1h44m
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17          1d
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20          45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17          54s
+
+
+
+-- timetable.txt --
+NAME  TIME
+foo   2024-11-18T12:00:00+01:00
+bar   2024-11-18T12:45:00+01:00
+sel   2024-07-18T12:00:00+01:00

t/test-stdin.txtar

@@ -0,0 +1,18 @@
+# reading from stdin and matching with lowercase words
+stdin testtable.txt
+exec tablizer -c name,status
+stdout grafana.*Runn
+
+# reading from -r stdin and matching with lowercase words
+stdin testtable.txt
+exec tablizer -c name,status -r -
+stdout grafana.*Runn
+
+# will be automatically created in work dir
+-- testtable.txt --
+NAME                                                 READY   STATUS    RESTARTS       AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35 (45m ago)   11d
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17 (45m ago)   1d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17 (45m ago)   1h44m
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20 (45m ago)   45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17 (45m ago)   54s

t/test-transpose.txtar

@@ -0,0 +1,21 @@
+# transpose one field
+exec tablizer -r testtable.txt -T status -R '/Running/OK/'
+stdout grafana.*OK
+
+# transpose two fields
+exec tablizer -r testtable.txt -T name,status -R '/alertmanager-//' -R '/Running/OK/' 
+stdout prometheus-0.*OK
+
+# transpose one field and show one column
+exec tablizer -r testtable.txt -T status -R '/Running/OK/' -c name
+! stdout grafana.*OK
+
+
+# will be automatically created in work dir
+-- testtable.txt --
+NAME                                                 READY   STATUS    RESTARTS       AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35 (45m ago)   11d
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17 (45m ago)   1d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17 (45m ago)   1h44m
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20 (45m ago)   45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17 (45m ago)   54s

t/test.sh

@@ -1,45 +0,0 @@
-#!/bin/sh
-
-# simple commandline unit test script
-
-t="../tablizer"
-fail=0
-
-ex() {
-    # execute a test, report+exit on error, stay silent otherwise
-    log="/tmp/test-tablizer.$$.log"
-    name=$1
-    shift
-
-    echo -n "TEST $name "
-
-    $* > $log 2>&1
-
-    if test $? -ne 0; then
-        echo "failed, see $log"
-        fail=1
-    else
-        echo "ok"
-        rm -f $log
-    fi
-}
-
-# only use files in test dir
-cd $(dirname $0)
-
-echo "Executing commandline tests ..."
-
-# io pattern tests
-ex io-pattern-and-file $t bk7 testtable
-cat testtable | ex io-pattern-and-stdin $t bk7
-cat testtable | ex io-pattern-and-stdin-dash $t bk7 -
-
-# same w/o pattern
-ex io-just-file $t testtable
-cat testtable | ex io-just-stdin $t
-cat testtable | ex io-just-stdin-dash $t -
-
-if test $fail -ne 0; then
-    echo "!!! Some tests failed !!!"
-    exit 1
-fi

t/testtable.csv

@@ -0,0 +1,6 @@
+NAME,DURATION
+x,10
+a,100
+z,0
+u,4
+k,6

t/testtable3

@@ -0,0 +1,6 @@
+NAME                                                 READY   STATUS    STARTS      AGE
+alertmanager-kube-prometheus-alertmanager-0          2/2     Running   35          11d
+kube-prometheus-blackbox-exporter-5d85b5d8f4-tskh7   1/1     Running   17          1h44m
+grafana-fcc54cbc9-bk7s8                              1/1     Running   17          1d
+kube-prometheus-kube-state-metrics-b4cd9487-75p7f    1/1     Running   20          45m
+kube-prometheus-node-exporter-bfzpl                  1/1     Running   17          54s

t/testtable4

@@ -0,0 +1,4 @@
+ONE  TWO
+1    4
+3    1
+5    2

t/testtable5

@@ -0,0 +1,6 @@
+SPECIES   TYPE         HOME     STAGE
+human     invasive     earth    brink
+riedl     peaceful     keauna   civilized
+namak     invasive     namak    imperium
+heduu     peaceful     iu       imperium
+kenaha    peaceful     kohi     hunter-gatherer

tablizer.1

@@ -133,7 +133,7 @@
 .\" ========================================================================
 .\"
 .IX Title "TABLIZER 1"
-.TH TABLIZER 1 "2023-11-22" "1" "User Commands"
+.TH TABLIZER 1 "2025-01-30" "1" "User Commands"
 .\" For nroff, turn off justification.  Always turn off hyphenation; it makes
 .\" way too many mistakes in technical documents.
 .if n .ad l
@@ -144,41 +144,44 @@ tablizer \- Manipulate tabular output of other programs
 .IX Header "SYNOPSIS"
 .Vb 2
 \&    Usage:
-\&      tablizer [regex] [file, ...] [flags]
+\&      tablizer [regex,...] [file, ...] [flags]
 \&    
 \&    Operational Flags:
-\&      \-c, \-\-columns string     Only show the speficied columns (separated by ,)
-\&      \-v, \-\-invert\-match       select non\-matching rows
-\&      \-n, \-\-no\-numbering       Disable header numbering
-\&      \-N, \-\-no\-color           Disable pattern highlighting
-\&      \-H, \-\-no\-headers         Disable headers display
-\&      \-s, \-\-separator string   Custom field separator
-\&      \-k, \-\-sort\-by int        Sort by column (default: 1)
-\&      \-z, \-\-fuzzy              Use fuzzy seach [experimental]
+\&      \-c, \-\-columns string              Only show the speficied columns (separated by ,)
+\&      \-v, \-\-invert\-match                select non\-matching rows
+\&      \-n, \-\-no\-numbering                Disable header numbering
+\&      \-N, \-\-no\-color                    Disable pattern highlighting
+\&      \-H, \-\-no\-headers                  Disable headers display
+\&      \-s, \-\-separator string            Custom field separator
+\&      \-k, \-\-sort\-by int|name            Sort by column (default: 1)
+\&      \-z, \-\-fuzzy                       Use fuzzy search [experimental]
+\&      \-F, \-\-filter field[!]=reg         Filter given field with regex, can be used multiple times
+\&      \-T, \-\-transpose\-columns string    Transpose the speficied columns (separated by ,)
+\&      \-R, \-\-regex\-transposer /from/to/  Apply /search/replace/ regexp to fields given in \-T
 \&
 \&    Output Flags (mutually exclusive):
-\&      \-X, \-\-extended           Enable extended output
-\&      \-M, \-\-markdown           Enable markdown table output
-\&      \-O, \-\-orgtbl             Enable org\-mode table output
-\&      \-S, \-\-shell              Enable shell evaluable output
-\&      \-Y, \-\-yaml               Enable yaml output
-\&      \-C, \-\-csv                Enable CSV output
-\&      \-A, \-\-ascii              Default output mode, ascii tabular
-\&      \-L, \-\-hightlight\-lines   Use alternating background colors for tables
+\&      \-X, \-\-extended                    Enable extended output
+\&      \-M, \-\-markdown                    Enable markdown table output
+\&      \-O, \-\-orgtbl                      Enable org\-mode table output
+\&      \-S, \-\-shell                       Enable shell evaluable output
+\&      \-Y, \-\-yaml                        Enable yaml output
+\&      \-C, \-\-csv                         Enable CSV output
+\&      \-A, \-\-ascii                       Default output mode, ascii tabular
+\&      \-L, \-\-hightlight\-lines            Use alternating background colors for tables
 \&
 \&    Sort Mode Flags (mutually exclusive):
-\&      \-a, \-\-sort\-age           sort according to age (duration) string
-\&      \-D, \-\-sort\-desc          Sort in descending order (default: ascending)
-\&      \-i, \-\-sort\-numeric       sort according to string numerical value
-\&      \-t, \-\-sort\-time          sort according to time string
+\&      \-a, \-\-sort\-age                    sort according to age (duration) string
+\&      \-D, \-\-sort\-desc                   Sort in descending order (default: ascending)
+\&      \-i, \-\-sort\-numeric                sort according to string numerical value
+\&      \-t, \-\-sort\-time                   sort according to time string
 \&
 \&    Other Flags:
-\&          \-\-completion <shell> Generate the autocompletion script for <shell>
-\&      \-f, \-\-config <file>      Configuration file (default: ~/.config/tablizer/config)
-\&      \-d, \-\-debug              Enable debugging
-\&      \-h, \-\-help               help for tablizer
-\&      \-m, \-\-man                Display manual page
-\&      \-V, \-\-version            Print program version
+\&          \-\-completion <shell>         Generate the autocompletion script for <shell>
+\&      \-f, \-\-config <file>              Configuration file (default: ~/.config/tablizer/config)
+\&      \-d, \-\-debug                      Enable debugging
+\&      \-h, \-\-help                       help for tablizer
+\&      \-m, \-\-man                        Display manual page
+\&      \-V, \-\-version                    Print program version
 .Ve
 .SH "DESCRIPTION"
 .IX Header "DESCRIPTION"
@@ -247,11 +250,20 @@ By  default, if  a  \fBpattern\fR  has been  speficied,  matches will  be
 highlighted. You can disable this behavior with the \fB\-N\fR option.
 .PP
 Use the  \fB\-k\fR option to specify  by which column to  sort the tabular
-data (as in \s-1GNU\s0 \fBsort\fR\|(1)). The default sort column is the first one. To
-disable sorting at all, supply 0  (Zero) to \-k. The default sort order
-is ascending. You can change this to descending order using the option
-\&\fB\-D\fR. The default  sort order is by string, but  there are other sort
-modes:
+data  (as in  \s-1GNU\s0  \fBsort\fR\|(1)).  The default  sort  column  is the  first
+one. You can specify column numbers or names. Column numbers start
+with 1, names are case insensitive. You can specify multiple columns
+separated by comma to sort, but the type must be the same. For example
+if you want to sort numerically, all columns must be numbers. If you
+use column numbers, then be aware, that these are the numbers before
+column extraction. For example if you have a table with 4 columns and
+specify \f(CW\*(C`\-c4\*(C'\fR, then only 1 column (the fourth) will be printed,
+however if you want to sort by this column, you'll have to specify
+\&\f(CW\*(C`\-k4\*(C'\fR.
+.PP
+The default  sort order  is ascending.  You can  change this  to
+descending order using the option \fB\-D\fR.  The default sort order is by
+alphanumeric string, but there are other sort modes:
 .IP "\fB\-a \-\-sort\-age\fR" 4
 .IX Item "-a --sort-age"
 Sorts duration strings like \*(L"1d4h32m51s\*(R".
@@ -264,42 +276,77 @@ Sorts timestamps.
 .PP
 Finally the  \fB\-d\fR option  enables debugging  output which  is mostly
 useful for the developer.
-.SS "\s-1PATTERNS\s0"
-.IX Subsection "PATTERNS"
-You can reduce the rows being  displayed by using a regular expression
-pattern.  The  regexp is  \s-1PCRE\s0 compatible, refer  to the  syntax cheat
-sheet here: <https://github.com/google/re2/wiki/Syntax>.  If you want
-to read  a more comprehensive  documentation about the topic  and have
-perl installed you can read it with:
+.SS "\s-1PATTERNS AND FILTERING\s0"
+.IX Subsection "PATTERNS AND FILTERING"
+You can reduce  the rows being displayed by using  one or more regular
+expression patterns.   The regexp  language being used  is the  one of
+\&\s-1GOLANG,\s0     refer    to     the    syntax     cheat    sheet     here:
+<https://pkg.go.dev/regexp/syntax>.
+.PP
+If you  want to  read a more  comprehensive documentation  about the
+topic and have perl installed you can read it with:
 .PP
 .Vb 1
 \&    perldoc perlre
 .Ve
 .PP
-Or read it online: <https://perldoc.perl.org/perlre>.
+Or read it online: <https://perldoc.perl.org/perlre>. But please note
+that the \s-1GO\s0 regexp engine does \s-1NOT\s0 support all perl regex terms,
+especially look-ahead and look-behind.
 .PP
-A note on  modifiers: the regexp engine used in  tablizer uses another
-modifier syntax:
+If you want to supply flags to a regex, then surround it with slashes
+and append the flag. The following flags are supported:
 .PP
-.Vb 1
-\&    (?MODIFIER)
+.Vb 2
+\&    i => case insensitive
+\&    ! => negative match
 .Ve
 .PP
-The most important modifiers are:
-.PP
-\&\f(CW\*(C`i\*(C'\fR ignore case
-\&\f(CW\*(C`m\*(C'\fR multiline mode
-\&\f(CW\*(C`s\*(C'\fR single line mode
-.PP
 Example for a case insensitive search:
 .PP
 .Vb 1
-\&    kubectl get pods \-A | tablizer "(?i)account"
+\&    kubectl get pods \-A | tablizer "/account/i"
 .Ve
 .PP
-You  can use  the experimental  fuzzy seach  feature by  providing the
+If you use the \f(CW\*(C`!\*(C'\fR flag, then the regex match will be negated, that
+is, if a line in the input matches the given regex, but \f(CW\*(C`!\*(C'\fR is
+supplied, tablizer will \s-1NOT\s0 include it in the output.
+.PP
+For example, here we want to get all lines matching \*(L"foo\*(R" but not
+\&\*(L"bar\*(R":
+.PP
+.Vb 1
+\&    cat table | tablizer foo \*(Aq/bar/!\*(Aq
+.Ve
+.PP
+This would match a line \*(L"foo zorro\*(R" but not \*(L"foo bar\*(R".
+.PP
+The flags can also be combined.
+.PP
+You  can also use  the experimental  fuzzy search  feature by  providing the
 option \fB\-z\fR, in which case the  pattern is regarded as a fuzzy search
 term, not a regexp.
+.PP
+Sometimes you want to  filter by one or more columns.  You can do that
+using the \fB\-F\fR option. The option can be specified multiple times and
+has the following format:
+.PP
+.Vb 1
+\&    fieldname=regexp
+.Ve
+.PP
+Fieldnames (== columns headers) are case insensitive.
+.PP
+If you specify more than one filter, both filters have to match (\s-1AND\s0
+operation).
+.PP
+These field filters can also be negated:
+.PP
+.Vb 1
+\&    fieldname!=regexp
+.Ve
+.PP
+If the option \fB\-v\fR is specified, the filtering is inverted.
 .SS "\s-1COLUMNS\s0"
 .IX Subsection "COLUMNS"
 The  parameter  \fB\-c\fR  can  be  used  to  specify,  which  columns  to
@@ -332,6 +379,50 @@ We want to see only the \s-1CMD\s0 column and use a regex for this:
 .Ve
 .PP
 where \*(L"C\*(R" is our regexp which matches \s-1CMD.\s0
+.PP
+If a column specifier doesn't look like a regular expression, matching
+against header  fields will  be case  insensitive. So,  if you  have a
+field with  the name \f(CW\*(C`ID\*(C'\fR then  these will all match:  \f(CW\*(C`\-c id\*(C'\fR, \f(CW\*(C`\-c
+Id\*(C'\fR. The same rule applies to the options \f(CW\*(C`\-T\*(C'\fR and \f(CW\*(C`\-F\*(C'\fR.
+.SS "\s-1TRANSPOSE FIELDS USING REGEXPS\s0"
+.IX Subsection "TRANSPOSE FIELDS USING REGEXPS"
+You can manipulate field contents using regular expressions. You have
+to tell tablizer which field[s] to operate on using the option \f(CW\*(C`\-T\*(C'\fR
+and the search/replace pattern using \f(CW\*(C`\-R\*(C'\fR. The number of columns and
+patterns must match.
+.PP
+A search/replace pattern consists of the following elements:
+.PP
+.Vb 1
+\&    /search\-regexp/replace\-string/
+.Ve
+.PP
+The separator can be any valid character. Especially if you want to
+use a regexp containing the \f(CW\*(C`/\*(C'\fR character, eg:
+.PP
+.Vb 1
+\&    |search\-regexp|replace\-string|
+.Ve
+.PP
+Example:
+.PP
+.Vb 7
+\&    cat t/testtable2
+\&    NAME  DURATION
+\&    x     10
+\&    a     100
+\&    z     0
+\&    u     4
+\&    k     6
+\&    
+\&    cat t/testtable2 | tablizer \-T2 \-R \*(Aq/^\ed/4/\*(Aq \-n
+\&    NAME    DURATION 
+\&    x       40      
+\&    a       400     
+\&    z       4       
+\&    u       4       
+\&    k       4
+.Ve
 .SS "\s-1OUTPUT MODES\s0"
 .IX Subsection "OUTPUT MODES"
 There might be cases  when the tabular output of a  program is way too
@@ -487,7 +578,7 @@ or to submit a patch, please open an issue on github:
 .IX Header "LICENSE"
 This software is licensed under the \s-1GNU GENERAL PUBLIC LICENSE\s0 version 3.
 .PP
-Copyright (c) 2023 by Thomas von Dein
+Copyright (c) 2022\-2024 by Thomas von Dein
 .PP
 This software uses the following \s-1GO\s0 modules:
 .IP "repr (https://github.com/alecthomas/repr)" 4

tablizer.pod

@@ -5,41 +5,44 @@ tablizer - Manipulate tabular output of other programs
 =head1 SYNOPSIS
 
     Usage:
-      tablizer [regex] [file, ...] [flags]
+      tablizer [regex,...] [file, ...] [flags]
     
     Operational Flags:
-      -c, --columns string     Only show the speficied columns (separated by ,)
-      -v, --invert-match       select non-matching rows
-      -n, --no-numbering       Disable header numbering
-      -N, --no-color           Disable pattern highlighting
-      -H, --no-headers         Disable headers display
-      -s, --separator string   Custom field separator
-      -k, --sort-by int        Sort by column (default: 1)
-      -z, --fuzzy              Use fuzzy seach [experimental]
+      -c, --columns string              Only show the speficied columns (separated by ,)
+      -v, --invert-match                select non-matching rows
+      -n, --no-numbering                Disable header numbering
+      -N, --no-color                    Disable pattern highlighting
+      -H, --no-headers                  Disable headers display
+      -s, --separator string            Custom field separator
+      -k, --sort-by int|name            Sort by column (default: 1)
+      -z, --fuzzy                       Use fuzzy search [experimental]
+      -F, --filter field[!]=reg         Filter given field with regex, can be used multiple times
+      -T, --transpose-columns string    Transpose the speficied columns (separated by ,)
+      -R, --regex-transposer /from/to/  Apply /search/replace/ regexp to fields given in -T
 
     Output Flags (mutually exclusive):
-      -X, --extended           Enable extended output
-      -M, --markdown           Enable markdown table output
-      -O, --orgtbl             Enable org-mode table output
-      -S, --shell              Enable shell evaluable output
-      -Y, --yaml               Enable yaml output
-      -C, --csv                Enable CSV output
-      -A, --ascii              Default output mode, ascii tabular
-      -L, --hightlight-lines   Use alternating background colors for tables
+      -X, --extended                    Enable extended output
+      -M, --markdown                    Enable markdown table output
+      -O, --orgtbl                      Enable org-mode table output
+      -S, --shell                       Enable shell evaluable output
+      -Y, --yaml                        Enable yaml output
+      -C, --csv                         Enable CSV output
+      -A, --ascii                       Default output mode, ascii tabular
+      -L, --hightlight-lines            Use alternating background colors for tables
 
     Sort Mode Flags (mutually exclusive):
-      -a, --sort-age           sort according to age (duration) string
-      -D, --sort-desc          Sort in descending order (default: ascending)
-      -i, --sort-numeric       sort according to string numerical value
-      -t, --sort-time          sort according to time string
+      -a, --sort-age                    sort according to age (duration) string
+      -D, --sort-desc                   Sort in descending order (default: ascending)
+      -i, --sort-numeric                sort according to string numerical value
+      -t, --sort-time                   sort according to time string
 
     Other Flags:
-          --completion <shell> Generate the autocompletion script for <shell>
-      -f, --config <file>      Configuration file (default: ~/.config/tablizer/config)
-      -d, --debug              Enable debugging
-      -h, --help               help for tablizer
-      -m, --man                Display manual page
-      -V, --version            Print program version
+          --completion <shell>         Generate the autocompletion script for <shell>
+      -f, --config <file>              Configuration file (default: ~/.config/tablizer/config)
+      -d, --debug                      Enable debugging
+      -h, --help                       help for tablizer
+      -m, --man                        Display manual page
+      -V, --version                    Print program version
 
 
 =head1 DESCRIPTION
@@ -103,11 +106,20 @@ By  default, if  a  B<pattern>  has been  speficied,  matches will  be
 highlighted. You can disable this behavior with the B<-N> option.
 
 Use the  B<-k> option to specify  by which column to  sort the tabular
-data (as in GNU sort(1)). The default sort column is the first one. To
-disable sorting at all, supply 0  (Zero) to -k. The default sort order
-is ascending. You can change this to descending order using the option
-B<-D>. The default  sort order is by string, but  there are other sort
-modes:
+data  (as in  GNU  sort(1)).  The default  sort  column  is the  first
+one. You can specify column numbers or names. Column numbers start
+with 1, names are case insensitive. You can specify multiple columns
+separated by comma to sort, but the type must be the same. For example
+if you want to sort numerically, all columns must be numbers. If you
+use column numbers, then be aware, that these are the numbers before
+column extraction. For example if you have a table with 4 columns and
+specify C<-c4>, then only 1 column (the fourth) will be printed,
+however if you want to sort by this column, you'll have to specify
+C<-k4>.
+
+The default  sort order  is ascending.  You can  change this  to
+descending order using the option B<-D>.  The default sort order is by
+alphanumeric string, but there are other sort modes:
 
 =over
 
@@ -128,37 +140,67 @@ Sorts timestamps.
 Finally the  B<-d> option  enables debugging  output which  is mostly
 useful for the developer.
 
-=head2 PATTERNS
+=head2 PATTERNS AND FILTERING
 
-You can reduce the rows being  displayed by using a regular expression
-pattern.  The  regexp is  PCRE compatible, refer  to the  syntax cheat
-sheet here: L<https://github.com/google/re2/wiki/Syntax>.  If you want
-to read  a more comprehensive  documentation about the topic  and have
-perl installed you can read it with:
+You can reduce  the rows being displayed by using  one or more regular
+expression patterns.   The regexp  language being used  is the  one of
+GOLANG,     refer    to     the    syntax     cheat    sheet     here:
+L<https://pkg.go.dev/regexp/syntax>.
+
+If you  want to  read a more  comprehensive documentation  about the
+topic and have perl installed you can read it with:
 
     perldoc perlre
 
-Or read it online: L<https://perldoc.perl.org/perlre>.
+Or read it online: L<https://perldoc.perl.org/perlre>. But please note
+that the GO regexp engine does NOT support all perl regex terms,
+especially look-ahead and look-behind.
 
-A note on  modifiers: the regexp engine used in  tablizer uses another
-modifier syntax:
+If you want to supply flags to a regex, then surround it with slashes
+and append the flag. The following flags are supported:
 
-    (?MODIFIER)
-
-The most important modifiers are:
-
-C<i> ignore case
-C<m> multiline mode
-C<s> single line mode
+    i => case insensitive
+    ! => negative match
 
 Example for a case insensitive search:
 
-    kubectl get pods -A | tablizer "(?i)account"
+    kubectl get pods -A | tablizer "/account/i"
 
-You  can use  the experimental  fuzzy seach  feature by  providing the
+If you use the C<!> flag, then the regex match will be negated, that
+is, if a line in the input matches the given regex, but C<!> is
+supplied, tablizer will NOT include it in the output.
+
+For example, here we want to get all lines matching "foo" but not
+"bar":
+
+    cat table | tablizer foo '/bar/!'
+
+This would match a line "foo zorro" but not "foo bar".
+
+The flags can also be combined.
+
+You  can also use  the experimental  fuzzy search  feature by  providing the
 option B<-z>, in which case the  pattern is regarded as a fuzzy search
 term, not a regexp.
 
+Sometimes you want to  filter by one or more columns.  You can do that
+using the B<-F> option. The option can be specified multiple times and
+has the following format:
+
+    fieldname=regexp
+
+Fieldnames (== columns headers) are case insensitive.
+
+If you specify more than one filter, both filters have to match (AND
+operation).
+
+These field filters can also be negated:
+
+    fieldname!=regexp
+
+If the option B<-v> is specified, the filtering is inverted.
+
+
 =head2 COLUMNS
 
 The  parameter  B<-c>  can  be  used  to  specify,  which  columns  to
@@ -188,6 +230,46 @@ We want to see only the CMD column and use a regex for this:
 
 where "C" is our regexp which matches CMD.
 
+If a column specifier doesn't look like a regular expression, matching
+against header  fields will  be case  insensitive. So,  if you  have a
+field with  the name C<ID> then  these will all match:  C<-c id>, C<-c
+Id>. The same rule applies to the options C<-T> and C<-F>.
+
+
+=head2 TRANSPOSE FIELDS USING REGEXPS
+
+You can manipulate field contents using regular expressions. You have
+to tell tablizer which field[s] to operate on using the option C<-T>
+and the search/replace pattern using C<-R>. The number of columns and
+patterns must match.
+
+A search/replace pattern consists of the following elements:
+
+    /search-regexp/replace-string/
+
+The separator can be any valid character. Especially if you want to
+use a regexp containing the C</> character, eg:
+
+    |search-regexp|replace-string|
+
+Example:
+    
+    cat t/testtable2
+    NAME  DURATION
+    x     10
+    a     100
+    z     0
+    u     4
+    k     6
+    
+    cat t/testtable2 | tablizer -T2 -R '/^\d/4/' -n
+    NAME    DURATION 
+    x       40      
+    a       400     
+    z       4       
+    u       4       
+    k       4  
+
 =head2 OUTPUT MODES
 
 There might be cases  when the tabular output of a  program is way too
@@ -326,6 +408,8 @@ the C<-L> parameter).
 Colorization can be turned off completely either by setting the
 parameter C<-N> or the environment variable B<NO_COLOR> to a true value.
 
+
+
 =head1 BUGS
 
 In order to report a bug, unexpected behavior, feature requests
@@ -336,7 +420,7 @@ L<https://github.com/TLINDEN/tablizer/issues>.
 
 This software is licensed under the GNU GENERAL PUBLIC LICENSE version 3.
 
-Copyright (c) 2023 by Thomas von Dein
+Copyright (c) 2022-2024 by Thomas von Dein
 
 This software uses the following GO modules: