add json output mode (-J) (#87)

* fix #77: parse floats and nils as well and convert them to string

.github/workflows/ci.yaml

@@ -1,16 +1,16 @@
 name: build-and-test-tablizer
-on: [push, pull_request]
+on: [push]
 jobs:
   build:
     strategy:
       matrix:
-        version: ['1.23']
+        version: ['1.24']
         os: [ubuntu-latest, macos-latest, windows-latest]
     name: Build
     runs-on: ${{ matrix.os }}
     steps:
     - name: Set up Go ${{ matrix.version }}
-      uses: actions/setup-go@v5
+      uses: actions/setup-go@v6
       with:
         go-version: '${{ matrix.version }}'
       id: go
@@ -28,9 +28,9 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
-          go-version: 1.23
+          go-version: 1.24
       - uses: actions/checkout@v5
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v6

.github/workflows/release.yaml

@@ -13,9 +13,9 @@ jobs:
         uses: actions/checkout@v5
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
-          go-version: 1.22.11
+          go-version: 1.24.0
 
       - name: Build the executables
         run: ./mkrel.sh tablizer ${{ github.ref_name}}

Makefile

@@ -65,7 +65,7 @@ clean:
 	rm -rf $(tool) releases coverage.out
 
 test: clean
-	go test ./... $(OPTS)
+	go test -count=1 -cover ./... $(OPTS)
 
 singletest:
 	@echo "Call like this: 'make singletest TEST=TestPrepareColumns MOD=lib'"

README.md

@@ -11,6 +11,23 @@ ignore certain column[s] by regex, name or number. It can output the
 tabular data in a range of formats (see below). There's even an
 interactive filter/selection tool available.
 
+## FEATURES
+
+- supports csv, json or ascii format input from files or stdin
+- split any tabular input data by character or regular expression into columns
+- add headers if input data doesn't contain them (automatically or manually)
+- print tabular data as ascii table, org-mode, markdown, csv, shell-evaluable or yaml format
+- filter rows by regular expression (saves a call to `| grep ...`)
+- filter rows by column filter
+- filters may also be negations eg `-Fname!=cow.*` or `-v`
+- modify cells wih regular expressions
+- reduce columns by specifying which columns to show, with regex support
+- color support
+- sort by any field[s], multiple sort modes are supported
+- shell completion for options
+- regular used options can be put into a config file
+- filter TUI where where you can interactively sort and filter rows
+
 ## Demo
 
 ![demo cast](vhsdemo/demo.gif)
@@ -34,7 +51,11 @@ Operational Flags:
   -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
+  -j, --json                         Read JSON input (must be array of hashes)
   -I, --interactive                  Interactively filter and select rows
+      --auto-headers                 Generate headers if there are none present in input
+      --custom-headers a,b,...       Use custom headers, separated by comma
+
 
 Output Flags (mutually exclusive):
   -X, --extended                     Enable extended output
@@ -191,10 +212,9 @@ hesitate to ask me about it, I'll add it.
 ## Documentation
 
 The  documentation  is  provided  as  a unix  man-page.   It  will  be
-automatically installed if  you install from source.  However, you can
-read the man-page online:
+automatically installed if  you install from source.
 
-https://github.com/TLINDEN/tablizer/blob/main/tablizer.pod
+[However, you can read the man-page online](https://github.com/TLINDEN/tablizer/blob/main/tablizer.pod).
 
 Or if you cloned  the repository you can read it  this way (perl needs
 to be installed though): `perldoc tablizer.pod`.

cfg/config.go

@@ -27,13 +27,26 @@ import (
 	"github.com/hashicorp/hcl/v2/hclsimple"
 )
 
-const DefaultSeparator string = `(\s\s+|\t)`
-const Version string = "v1.5.5"
-const MAXPARTS = 2
+const (
+	Version  = "v1.5.11"
+	MAXPARTS = 2
+)
 
-var DefaultConfigfile = os.Getenv("HOME") + "/.config/tablizer/config"
+var (
+	DefaultConfigfile = os.Getenv("HOME") + "/.config/tablizer/config"
+	VERSION           string // maintained by -x
 
-var VERSION string // maintained by -x
+	SeparatorTemplates = map[string]string{
+		":tab:":      `\s*\t\s*`,                               // tab but eats spaces around
+		":spaces:":   `\s{2,}`,                                 // 2 or more spaces
+		":pipe:":     `\s*\|\s*`,                               // one pipe eating spaces around
+		":default:":  `(\s\s+|\t)`,                             // 2 or more spaces or tab
+		":nonword:":  `\W`,                                     // word boundary
+		":nondigit:": `\D`,                                     // same for numbers
+		":special:":  `[\*\+\-_\(\)\[\]\{\}?\\/<>=&$§"':,\^]+`, // match any special char
+		":nonprint:": `[[:^print:]]+`,                          // non printables
+	}
+)
 
 // public config, set via config file or using defaults
 type Settings struct {
@@ -79,6 +92,9 @@ type Config struct {
 	UseFuzzySearch bool
 	UseHighlight   bool
 	Interactive    bool
+	InputJSON      bool
+	AutoHeaders    bool
+	CustomHeaders  []string
 
 	SortMode        string
 	SortDescending  bool
@@ -125,6 +141,7 @@ type Modeflag struct {
 	Y bool
 	A bool
 	C bool
+	J bool
 }
 
 // used for switching printers
@@ -136,6 +153,7 @@ const (
 	Yaml
 	CSV
 	ASCII
+	Json
 )
 
 // various sort types
@@ -274,6 +292,8 @@ func (conf *Config) PrepareModeFlags(flag Modeflag) {
 		conf.OutputMode = Yaml
 	case flag.C:
 		conf.OutputMode = CSV
+	case flag.J:
+		conf.OutputMode = Json
 	default:
 		conf.OutputMode = ASCII
 	}
@@ -355,6 +375,13 @@ func (conf *Config) ApplyDefaults() {
 	if conf.OutputMode == Yaml || conf.OutputMode == CSV {
 		conf.Numbering = false
 	}
+
+	if conf.Separator[0] == ':' && conf.Separator[len(conf.Separator)-1] == ':' {
+		separator, ok := SeparatorTemplates[conf.Separator]
+		if ok {
+			conf.Separator = separator
+		}
+	}
 }
 
 func (conf *Config) PreparePattern(patterns []*Pattern) error {
@@ -392,6 +419,12 @@ func (conf *Config) PreparePattern(patterns []*Pattern) error {
 	return nil
 }
 
+func (conf *Config) PrepareCustomHeaders(custom string) {
+	if len(custom) > 0 {
+		conf.CustomHeaders = strings.Split(custom, ",")
+	}
+}
+
 // 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 {

cfg/config_test.go

@@ -21,6 +21,8 @@ import (
 	"fmt"
 	//	"reflect"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestPrepareModeFlags(t *testing.T) {
@@ -44,9 +46,8 @@ func TestPrepareModeFlags(t *testing.T) {
 			conf := Config{}
 
 			conf.PrepareModeFlags(testdata.flag)
-			if conf.OutputMode != testdata.expect {
-				t.Errorf("got: %d, expect: %d", conf.OutputMode, testdata.expect)
-			}
+
+			assert.EqualValues(t, testdata.expect, conf.OutputMode)
 		})
 	}
 }
@@ -70,9 +71,7 @@ func TestPrepareSortFlags(t *testing.T) {
 
 			conf.PrepareSortFlags(testdata.flag)
 
-			if conf.SortMode != testdata.expect {
-				t.Errorf("got: %s, expect: %s", conf.SortMode, testdata.expect)
-			}
+			assert.EqualValues(t, testdata.expect, conf.SortMode)
 		})
 	}
 }
@@ -81,7 +80,7 @@ func TestPreparePattern(t *testing.T) {
 	var tests = []struct {
 		patterns  []*Pattern
 		name      string
-		wanterr   bool
+		wanterror bool
 		wanticase bool
 		wantneg   bool
 	}{
@@ -123,16 +122,16 @@ func TestPreparePattern(t *testing.T) {
 	}
 
 	for _, testdata := range tests {
-		testname := fmt.Sprintf("PreparePattern-pattern-%s-wanterr-%t", testdata.name, testdata.wanterr)
+		testname := fmt.Sprintf("PreparePattern-pattern-%s-wanterr-%t", testdata.name, testdata.wanterror)
 		t.Run(testname, func(t *testing.T) {
 			conf := Config{}
 
 			err := conf.PreparePattern(testdata.patterns)
 
-			if err != nil {
-				if !testdata.wanterr {
-					t.Errorf("PreparePattern returned error: %s", err)
-				}
+			if testdata.wanterror {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
 			}
 		})
 	}

cmd/root.go

@@ -20,6 +20,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"slices"
 	"strings"
 
 	"github.com/spf13/cobra"
@@ -58,6 +59,7 @@ func Execute() {
 		ShowCompletion string
 		modeflag       cfg.Modeflag
 		sortmode       cfg.Sortmode
+		headers        string
 	)
 
 	var rootCmd = &cobra.Command{
@@ -90,6 +92,7 @@ func Execute() {
 			conf.CheckEnv()
 			conf.PrepareModeFlags(modeflag)
 			conf.PrepareSortFlags(sortmode)
+			conf.PrepareCustomHeaders(headers)
 
 			wrapE(conf.PrepareFilters())
 
@@ -122,7 +125,7 @@ func Execute() {
 		"Use alternating background colors")
 	rootCmd.PersistentFlags().StringVarP(&ShowCompletion, "completion", "", "",
 		"Display completion code")
-	rootCmd.PersistentFlags().StringVarP(&conf.Separator, "separator", "s", cfg.DefaultSeparator,
+	rootCmd.PersistentFlags().StringVarP(&conf.Separator, "separator", "s", cfg.SeparatorTemplates[":default:"],
 		"Custom field separator")
 	rootCmd.PersistentFlags().StringVarP(&conf.Columns, "columns", "c", "",
 		"Only show the speficied columns (separated by ,)")
@@ -131,9 +134,15 @@ func Execute() {
 	rootCmd.PersistentFlags().StringVarP(&conf.TransposeColumns, "transpose-columns", "T", "",
 		"Transpose the speficied columns (separated by ,)")
 	rootCmd.PersistentFlags().BoolVarP(&conf.Interactive, "interactive", "I", false,
-		"interactive mode (experimental)")
-	rootCmd.PersistentFlags().StringVarP(&conf.OFS, "ofs", "", "",
+		"interactive mode")
+	rootCmd.PersistentFlags().StringVarP(&conf.OFS, "ofs", "o", "",
 		"Output field separator (' ' for ascii table, ',' for CSV)")
+	rootCmd.PersistentFlags().BoolVarP(&conf.InputJSON, "json", "j", false,
+		"JSON input mode")
+	rootCmd.PersistentFlags().BoolVarP(&conf.AutoHeaders, "auto-headers", "g", false,
+		"Generate headers automatically")
+	rootCmd.PersistentFlags().StringVarP(&headers, "custom-headers", "x", "",
+		"Custom headers")
 
 	// sort options
 	rootCmd.PersistentFlags().StringVarP(&conf.SortByColumn, "sort-by", "k", "",
@@ -162,6 +171,8 @@ func Execute() {
 		"Enable shell mode output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.Y, "yaml", "Y", false,
 		"Enable yaml output")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.J, "jsonout", "J", false,
+		"Enable json output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.C, "csv", "C", false,
 		"Enable CSV output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.A, "ascii", "A", false,
@@ -185,6 +196,11 @@ func Execute() {
 
 	rootCmd.SetUsageTemplate(strings.TrimSpace(usage) + "\n")
 
+	if slices.Contains(os.Args, "-h") {
+		fmt.Println(shortusage)
+		os.Exit(0)
+	}
+
 	err := rootCmd.Execute()
 	if err != nil {
 		os.Exit(1)

cmd/shortusage.go

@@ -0,0 +1,18 @@
+package cmd
+
+const shortusage = `tablizer [regex,...] [-r file] [flags]
+-c col,...   show specified columns                  -L  highlight matching lines
+-k col,...   sort by specified columns               -j  read JSON input
+-F col=reg   filter field with regexp                -v  invert match
+-T col,...   transpose specified columns             -n  numberize columns
+-R /from/to/ apply replacement to columns in -T      -N  do not use colors
+-y col,...   yank columns to clipboard               -H  do not show headers
+--ofs char   output field separator                  -s  specify field separator
+-r file      read input from file                    -z  use fuzzy search
+-f file      read config from file                   -I  interactive filter mode
+-x col,...   use custom headers                      -d  debug
+-o char      use char as output separator            -g  auto generate headers
+
+-O org -C CSV -M md -X ext -S shell -Y yaml -J json  -D  sort descending order
+-m  show manual       --help  show detailed help     -v  show version
+-a  sort by age       -i      sort numerically       -t  sort by time`

cmd/tablizer.go

@@ -14,13 +14,16 @@ SYNOPSIS
           -n, --numbering                    Enable header numbering
           -N, --no-color                     Disable pattern highlighting
           -H, --no-headers                   Disable headers display
-          -s, --separator <string>           Custom field separator
+          -s, --separator <string>           Custom field separator (maybe char, string or :class:)
           -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
+          -j, --json                         Read JSON input (must be array of hashes)
           -I, --interactive                  Interactively filter and select rows
+          -g, --auto-headers                 Generate headers if there are none present in input
+          -x, --custom-headers a,b,...       Use custom headers, separated by comma
 
         Output Flags (mutually exclusive):
           -X, --extended                     Enable extended output
@@ -28,12 +31,13 @@ SYNOPSIS
           -O, --orgtbl                       Enable org-mode table output
           -S, --shell                        Enable shell evaluable output
           -Y, --yaml                         Enable yaml output
+          -J, --jsonout                      Enable JSON output
           -C, --csv                          Enable CSV output
           -A, --ascii                        Default output mode, ascii tabular
           -L, --hightlight-lines             Use alternating background colors for tables
+          -o, --ofs <char>                   Output field separator, used by -A and -C. 
           -y, --yank-columns                 Yank specified columns (separated by ,) to clipboard,
                                              space separated
-              --ofs <char>                   Output field separator, used by -A and -C. 
 
         Sort Mode Flags (mutually exclusive):
           -a, --sort-age                     sort according to age (duration) string
@@ -140,6 +144,57 @@ DESCRIPTION
     Finally the -d option enables debugging output which is mostly useful
     for the developer.
 
+  SEPARATOR
+    The option -s can be a single character, in which case the CSV parser
+    will be invoked. You can also specify a string as separator. The string
+    will be interpreted as literal string unless it is a valid go regular
+    expression. For example:
+
+        -s '\t{2,}\'
+
+    is being used as a regexp and will match two or more consecutive tabs.
+
+        -s 'foo'
+
+    on the other hand is no regular expression and will be used literally.
+
+    To make live easier, there are a couple of predefined regular
+    expressions, which you can specify as classes:
+
+        * :tab:
+
+        Matches a tab and eats spaces around it.
+
+        * :spaces:
+
+        Matches 2 or more spaces.
+
+        * :pipe:
+
+        Matches a pipe character and eats spaces around it.
+
+        * :default:
+
+        Matches 2 or more spaces or tab. This is the default separator if
+        none is specified.
+
+        * :nonword:
+
+        Matches a non-word character.
+
+        * :nondigit:
+
+        Matches a non-digit character.
+
+        * :special:
+
+        Matches one or more special chars like brackets, dollar sign,
+        slashes etc.
+
+        * :nonprint:
+
+        Matches one or more non-printable characters.
+
   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
@@ -457,13 +512,16 @@ Operational Flags:
   -n, --numbering                    Enable header numbering
   -N, --no-color                     Disable pattern highlighting
   -H, --no-headers                   Disable headers display
-  -s, --separator <string>           Custom field separator
+  -s, --separator <string>           Custom field separator (maybe char, string or :class:)
   -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
+  -j, --json                         Read JSON input (must be array of hashes)
   -I, --interactive                  Interactively filter and select rows
+  -g, --auto-headers                 Generate headers if there are none present in input
+  -x, --custom-headers a,b,...       Use custom headers, separated by comma
 
 Output Flags (mutually exclusive):
   -X, --extended                     Enable extended output
@@ -471,12 +529,13 @@ Output Flags (mutually exclusive):
   -O, --orgtbl                       Enable org-mode table output
   -S, --shell                        Enable shell evaluable output
   -Y, --yaml                         Enable yaml output
+  -J, --jsonout                      Enable JSON output
   -C, --csv                          Enable CSV output
   -A, --ascii                        Default output mode, ascii tabular
   -L, --hightlight-lines             Use alternating background colors for tables
+  -o, --ofs <char>                   Output field separator, used by -A and -C. 
   -y, --yank-columns                 Yank specified columns (separated by ,) to clipboard,
                                      space separated
-      --ofs <char>                   Output field separator, used by -A and -C. 
 
 Sort Mode Flags (mutually exclusive):
   -a, --sort-age                     sort according to age (duration) string

go.mod

@@ -1,22 +1,22 @@
 module github.com/tlinden/tablizer
 
-go 1.23.0
-
-toolchain go1.23.5
+go 1.24.0
 
 require (
-	github.com/alecthomas/repr v0.5.1
+	github.com/alecthomas/repr v0.5.2
 	github.com/araddon/dateparse v0.0.0-20210429162001-6b43995a97de
 	github.com/charmbracelet/bubbles v0.21.0
-	github.com/charmbracelet/bubbletea v1.3.6
+	github.com/charmbracelet/bubbletea v1.3.10
 	github.com/charmbracelet/lipgloss v1.1.0
-	github.com/evertras/bubble-table v0.19.0
+	github.com/evertras/bubble-table v0.19.2
 	github.com/gookit/color v1.6.0
 	github.com/hashicorp/hcl/v2 v2.24.0
 	github.com/lithammer/fuzzysearch v1.1.8
-	github.com/olekukonko/tablewriter v1.0.9
+	github.com/mattn/go-isatty v0.0.20
+	github.com/olekukonko/tablewriter v1.1.0
 	github.com/rogpeppe/go-internal v1.14.1
-	github.com/spf13/cobra v1.9.1
+	github.com/spf13/cobra v1.10.1
+	github.com/stretchr/testify v1.11.1
 	github.com/tiagomelo/go-clipboard v0.1.2
 	gopkg.in/yaml.v3 v3.0.1
 )
@@ -27,16 +27,16 @@ require (
 	github.com/atotto/clipboard v0.1.4 // indirect
 	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
 	github.com/charmbracelet/colorprofile v0.3.1 // indirect
-	github.com/charmbracelet/x/ansi v0.9.3 // indirect
+	github.com/charmbracelet/x/ansi v0.10.1 // indirect
 	github.com/charmbracelet/x/cellbuf v0.0.13 // indirect
 	github.com/charmbracelet/x/term v0.2.1 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f // indirect
 	github.com/fatih/color v1.18.0 // indirect
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
 	github.com/mattn/go-colorable v0.1.14 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-localereader v0.0.1 // indirect
 	github.com/mattn/go-runewidth v0.0.16 // indirect
 	github.com/mitchellh/go-wordwrap v1.0.1 // indirect
@@ -47,14 +47,15 @@ require (
 	github.com/olekukonko/errors v1.1.0 // indirect
 	github.com/olekukonko/ll v0.0.9 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
-	github.com/spf13/pflag v1.0.6 // indirect
+	github.com/spf13/pflag v1.0.9 // indirect
 	github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e // indirect
 	github.com/zclconf/go-cty v1.16.3 // indirect
 	golang.org/x/exp v0.0.0-20231006140011-7918f672742d // indirect
 	golang.org/x/mod v0.21.0 // indirect
 	golang.org/x/sync v0.15.0 // indirect
-	golang.org/x/sys v0.33.0 // indirect
+	golang.org/x/sys v0.36.0 // indirect
 	golang.org/x/text v0.25.0 // indirect
 	golang.org/x/tools v0.26.0 // indirect
 )

go.sum

@@ -1,7 +1,7 @@
 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 v0.5.1 h1:E3G4t2QbHTSNpPKBgMTln5KLkZHLOcU7r37J4pXBuIg=
-github.com/alecthomas/repr v0.5.1/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
+github.com/alecthomas/repr v0.5.2 h1:SU73FTI9D1P5UNtvseffFSGmdNci/O6RsqzeXJtP0Qs=
+github.com/alecthomas/repr v0.5.2/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
 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=
@@ -12,14 +12,14 @@ github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiE
 github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/charmbracelet/bubbles v0.21.0 h1:9TdC97SdRVg/1aaXNVWfFH3nnLAwOXr8Fn6u6mfQdFs=
 github.com/charmbracelet/bubbles v0.21.0/go.mod h1:HF+v6QUR4HkEpz62dx7ym2xc71/KBHg+zKwJtMw+qtg=
-github.com/charmbracelet/bubbletea v1.3.6 h1:VkHIxPJQeDt0aFJIsVxw8BQdh/F/L2KKZGsK6et5taU=
-github.com/charmbracelet/bubbletea v1.3.6/go.mod h1:oQD9VCRQFF8KplacJLo28/jofOI2ToOfGYeFgBBxHOc=
+github.com/charmbracelet/bubbletea v1.3.10 h1:otUDHWMMzQSB0Pkc87rm691KZ3SWa4KUlvF9nRvCICw=
+github.com/charmbracelet/bubbletea v1.3.10/go.mod h1:ORQfo0fk8U+po9VaNvnV95UPWA1BitP1E0N6xJPlHr4=
 github.com/charmbracelet/colorprofile v0.3.1 h1:k8dTHMd7fgw4bnFd7jXTLZrSU/CQrKnL3m+AxCzDz40=
 github.com/charmbracelet/colorprofile v0.3.1/go.mod h1:/GkGusxNs8VB/RSOh3fu0TJmQ4ICMMPApIIVn0KszZ0=
 github.com/charmbracelet/lipgloss v1.1.0 h1:vYXsiLHVkK7fp74RkV7b2kq9+zDLoEU4MZoFqR/noCY=
 github.com/charmbracelet/lipgloss v1.1.0/go.mod h1:/6Q8FR2o+kj8rz4Dq0zQc3vYf7X+B0binUUBwA0aL30=
-github.com/charmbracelet/x/ansi v0.9.3 h1:BXt5DHS/MKF+LjuK4huWrC6NCvHtexww7dMayh6GXd0=
-github.com/charmbracelet/x/ansi v0.9.3/go.mod h1:3RQDQ6lDnROptfpWuUVIUG64bD2g2BgntdxH0Ya5TeE=
+github.com/charmbracelet/x/ansi v0.10.1 h1:rL3Koar5XvX0pHGfovN03f5cxLbCF2YvLeyz7D2jVDQ=
+github.com/charmbracelet/x/ansi v0.10.1/go.mod h1:3RQDQ6lDnROptfpWuUVIUG64bD2g2BgntdxH0Ya5TeE=
 github.com/charmbracelet/x/cellbuf v0.0.13 h1:/KBBKHuVRbq1lYx5BzEHBAFBP8VcQzJejZ/IA3iR28k=
 github.com/charmbracelet/x/cellbuf v0.0.13/go.mod h1:xe0nKWGd3eJgtqZRaN9RjMtK7xUYchjzPr7q6kcvCCs=
 github.com/charmbracelet/x/term v0.2.1 h1:AQeHeLZ1OqSXhrAWpYUtZyX1T3zVxfpZuEQMIQaGIAQ=
@@ -30,8 +30,8 @@ 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/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f h1:Y/CXytFA4m6baUTXGLOoWe4PQhGxaX0KpnayAqC48p4=
 github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f/go.mod h1:vw97MGsxSvLiUE2X8qFplwetxpGLQrlU1Q9AUEIzCaM=
-github.com/evertras/bubble-table v0.19.0 h1:+JlXRUjNuBN1JI7XU1PapmW1wglbcqZUKkiPnVKPgrc=
-github.com/evertras/bubble-table v0.19.0/go.mod h1:ifHujS1YxwnYSOgcR2+m3GnJ84f7CVU/4kUOxUCjEbQ=
+github.com/evertras/bubble-table v0.19.2 h1:u77oiM6JlRR+CvS5FZc3Hz+J6iEsvEDcR5kO8OFb1Yw=
+github.com/evertras/bubble-table v0.19.2/go.mod h1:ifHujS1YxwnYSOgcR2+m3GnJ84f7CVU/4kUOxUCjEbQ=
 github.com/fatih/color v1.18.0 h1:S8gINlzdQ840/4pfAwic/ZE0djQEH3wM94VfqLTZcOM=
 github.com/fatih/color v1.18.0/go.mod h1:4FelSpRwEGDpQ12mAdzqdOukCy4u8WUtOY6lkT/6HfU=
 github.com/go-test/deep v1.0.3 h1:ZrJSEWsXzPOxaZnFteGEfooLba+ju3FYIbOrS+rQd68=
@@ -74,8 +74,8 @@ github.com/olekukonko/errors v1.1.0 h1:RNuGIh15QdDenh+hNvKrJkmxxjV4hcS50Db478Ou5
 github.com/olekukonko/errors v1.1.0/go.mod h1:ppzxA5jBKcO1vIpCXQ9ZqgDh8iwODz6OXIGKU8r5m4Y=
 github.com/olekukonko/ll v0.0.9 h1:Y+1YqDfVkqMWuEQMclsF9HUR5+a82+dxJuL1HHSRpxI=
 github.com/olekukonko/ll v0.0.9/go.mod h1:En+sEW0JNETl26+K8eZ6/W4UQ7CYSrrgg/EdIYT2H8g=
-github.com/olekukonko/tablewriter v1.0.9 h1:XGwRsYLC2bY7bNd93Dk51bcPZksWZmLYuaTHR0FqfL8=
-github.com/olekukonko/tablewriter v1.0.9/go.mod h1:5c+EBPeSqvXnLLgkm9isDdzR3wjfBkHR9Nhfp3NWrzo=
+github.com/olekukonko/tablewriter v1.1.0 h1:N0LHrshF4T39KvI96fn6GT8HEjXRXYNDrDjKFDB7RIY=
+github.com/olekukonko/tablewriter v1.1.0/go.mod h1:5c+EBPeSqvXnLLgkm9isDdzR3wjfBkHR9Nhfp3NWrzo=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -88,14 +88,14 @@ github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0t
 github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
 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/spf13/cobra v1.9.1 h1:CXSaggrXdbHK9CF+8ywj8Amf7PBRmPCOJugH954Nnlo=
-github.com/spf13/cobra v1.9.1/go.mod h1:nDyEzZ8ogv936Cinf6g1RU9MRY64Ir93oCnqb9wxYW0=
-github.com/spf13/pflag v1.0.6 h1:jFzHGLGAlb3ruxLB8MhbI6A8+AQX/2eW4qeyNZXNp2o=
-github.com/spf13/pflag v1.0.6/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/spf13/cobra v1.10.1 h1:lJeBwCfmrnXthfAupyUTzJ/J4Nc1RsHC/mSRU2dll/s=
+github.com/spf13/cobra v1.10.1/go.mod h1:7SmJGaTHFVBY0jW4NXGluQoLvhqFQM+6XSKD+P4XaB0=
+github.com/spf13/pflag v1.0.9 h1:9exaQaMOCwffKiiiYk6/BndUBv+iRViNW+4lEMi0PvY=
+github.com/spf13/pflag v1.0.9/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
-github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 github.com/tiagomelo/go-clipboard v0.1.2 h1:Ph2icR0vZRIj3v5ExvsGweBwsbbDUTlS6HoF40MkQD8=
 github.com/tiagomelo/go-clipboard v0.1.2/go.mod h1:kXtjJBIMimZaGbxmcKZ8+JqK+acSNf5tAJiChlZBOr8=
 github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e h1:JVG44RsyaB9T2KIHavMF/ppJZNG9ZpyihvCd0w101no=
@@ -130,8 +130,8 @@ golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBc
 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 v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.33.0 h1:q3i8TbbEz+JRD9ywIRlyRAQbM0qF7hu24q3teo2hbuw=
-golang.org/x/sys v0.33.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/sys v0.36.0 h1:KVRy2GtZBrk1cBYA7MKu5bEZFxQk4NIDV6RLVcC8o0k=
+golang.org/x/sys v0.36.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 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=

lib/filter_test.go

@@ -19,9 +19,9 @@ package lib
 
 import (
 	"fmt"
-	"reflect"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/tlinden/tablizer/cfg"
 )
 
@@ -56,13 +56,11 @@ func TestMatchPattern(t *testing.T) {
 			}
 
 			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")
-			}
+			assert.NoError(t, err)
+
+			res := matchPattern(conf, inputdata.line)
+			assert.EqualValues(t, true, res)
 		})
 	}
 }
@@ -163,14 +161,12 @@ func TestFilterByFields(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)
-			}
+
+			assert.NoError(t, 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)
-			}
+
+			assert.EqualValues(t, inputdata.expect, *data)
 		})
 	}
 }

lib/helpers.go

@@ -22,7 +22,7 @@ import (
 	"fmt"
 	"os"
 	"regexp"
-	"sort"
+	"slices"
 	"strconv"
 	"strings"
 
@@ -30,16 +30,6 @@ import (
 	"github.com/tlinden/tablizer/cfg"
 )
 
-func contains(s []int, e int) bool {
-	for _, a := range s {
-		if a == e {
-			return true
-		}
-	}
-
-	return false
-}
-
 func findindex(s []int, e int) (int, bool) {
 	for i, a := range s {
 		if a == e {
@@ -172,48 +162,32 @@ func PrepareColumnVars(columns string, data *Tabdata) ([]int, error) {
 		}
 	}
 
-	// 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))
+	// deduplicate columns, preserve order
+	deduped := []int{}
 	for _, i := range usecolumns {
-		imap[i] = 0
+		if !slices.Contains(deduped, i) {
+			deduped = append(deduped, i)
+		}
 	}
 
-	// fill with deduplicated columns
-	usecolumns = nil
-
-	for k := range imap {
-		usecolumns = append(usecolumns, k)
-	}
-
-	sort.Ints(usecolumns)
-
-	return usecolumns, nil
+	return deduped, nil
 }
 
 // prepare headers: add numbers to headers
 func numberizeAndReduceHeaders(conf cfg.Config, data *Tabdata) {
-	numberedHeaders := []string{}
+	numberedHeaders := make([]string, len(data.headers))
+
 	maxwidth := 0 // start from scratch, so we only look at displayed column widths
 
+	// add numbers to headers if needed, get widest cell width
 	for idx, head := range data.headers {
 		var headlen int
 
-		if len(conf.Columns) > 0 {
-			// -c specified
-			if !contains(conf.UseColumns, idx+1) {
-				// ignore this one
-				continue
-			}
-		}
-
 		if conf.Numbering {
-			numhead := fmt.Sprintf("%s(%d)", head, idx+1)
-			headlen = len(numhead)
-			numberedHeaders = append(numberedHeaders, numhead)
+			newhead := fmt.Sprintf("%s(%d)", head, idx+1)
+			numberedHeaders[idx] = newhead
+			headlen = len(newhead)
 		} else {
-			numberedHeaders = append(numberedHeaders, head)
 			headlen = len(head)
 		}
 
@@ -222,7 +196,24 @@ func numberizeAndReduceHeaders(conf cfg.Config, data *Tabdata) {
 		}
 	}
 
-	data.headers = numberedHeaders
+	if conf.Numbering {
+		data.headers = numberedHeaders
+	}
+
+	if len(conf.UseColumns) > 0 {
+		// re-align headers based on user requested column list
+		headers := make([]string, len(conf.UseColumns))
+
+		for i, col := range conf.UseColumns {
+			for idx := range data.headers {
+				if col-1 == idx {
+					headers[i] = data.headers[col-1]
+				}
+			}
+		}
+
+		data.headers = headers
+	}
 
 	if data.maxwidthHeader != maxwidth && maxwidth > 0 {
 		data.maxwidthHeader = maxwidth
@@ -234,17 +225,17 @@ func reduceColumns(conf cfg.Config, data *Tabdata) {
 	if len(conf.Columns) > 0 {
 		reducedEntries := [][]string{}
 
-		var reducedEntry []string
-
 		for _, entry := range data.entries {
-			reducedEntry = nil
+			var reducedEntry []string
 
-			for i, value := range entry {
-				if !contains(conf.UseColumns, i+1) {
-					continue
+			for _, col := range conf.UseColumns {
+				col--
+
+				for idx, value := range entry {
+					if idx == col {
+						reducedEntry = append(reducedEntry, value)
+					}
 				}
-
-				reducedEntry = append(reducedEntry, value)
 			}
 
 			reducedEntries = append(reducedEntries, reducedEntry)

lib/helpers_test.go

@@ -19,9 +19,10 @@ package lib
 
 import (
 	"fmt"
-	"reflect"
+	"slices"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/tlinden/tablizer/cfg"
 )
 
@@ -38,10 +39,9 @@ func TestContains(t *testing.T) {
 	for _, tt := range tests {
 		testname := fmt.Sprintf("contains-%d,%d,%t", tt.list, tt.search, tt.want)
 		t.Run(testname, func(t *testing.T) {
-			answer := contains(tt.list, tt.search)
-			if answer != tt.want {
-				t.Errorf("got %t, want %t", answer, tt.want)
-			}
+			answer := slices.Contains(tt.list, tt.search)
+
+			assert.EqualValues(t, tt.want, answer)
 		})
 	}
 }
@@ -73,18 +73,17 @@ func TestPrepareColumns(t *testing.T) {
 	}
 
 	for _, testdata := range tests {
-		testname := fmt.Sprintf("PrepareColumns-%s-%t", testdata.input, testdata.wanterror)
+		testname := fmt.Sprintf("PrepareColumns-%s-%t",
+			testdata.input, testdata.wanterror)
 		t.Run(testname, func(t *testing.T) {
 			conf := cfg.Config{Columns: testdata.input}
 			err := PrepareColumns(&conf, &data)
-			if err != nil {
-				if !testdata.wanterror {
-					t.Errorf("got error: %v", err)
-				}
+
+			if testdata.wanterror {
+				assert.Error(t, err)
 			} else {
-				if !reflect.DeepEqual(conf.UseColumns, testdata.exp) {
-					t.Errorf("got: %v, expected: %v", conf.UseColumns, testdata.exp)
-				}
+				assert.NoError(t, err)
+				assert.EqualValues(t, testdata.exp, conf.UseColumns)
 			}
 		})
 	}
@@ -153,18 +152,13 @@ func TestPrepareTransposerColumns(t *testing.T) {
 		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)
-				}
+			if testdata.wanterror {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.EqualValues(t, testdata.exp, len(conf.UseTransposeColumns))
+				assert.EqualValues(t, len(conf.UseTransposeColumns), len(conf.Transposers))
 			}
 		})
 	}
@@ -202,10 +196,8 @@ func TestReduceColumns(t *testing.T) {
 			c := cfg.Config{Columns: "x", UseColumns: testdata.columns}
 			data := Tabdata{entries: input}
 			reduceColumns(c, &data)
-			if !reflect.DeepEqual(data.entries, testdata.expect) {
-				t.Errorf("reduceColumns returned invalid data:\ngot: %+v\nexp: %+v",
-					data.entries, testdata.expect)
-			}
+
+			assert.EqualValues(t, testdata.expect, data.entries)
 		})
 	}
 }
@@ -233,10 +225,8 @@ func TestNumberizeHeaders(t *testing.T) {
 			conf := cfg.Config{Columns: "x", UseColumns: testdata.columns, Numbering: testdata.numberize}
 			usedata := data
 			numberizeAndReduceHeaders(conf, &usedata)
-			if !reflect.DeepEqual(usedata.headers, testdata.expect) {
-				t.Errorf("numberizeAndReduceHeaders returned invalid data:\ngot: %+v\nexp: %+v",
-					usedata.headers, testdata.expect)
-			}
+
+			assert.EqualValues(t, testdata.expect, usedata.headers)
 		})
 	}
 }

lib/parser.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2022-2024 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
@@ -20,8 +20,12 @@ package lib
 import (
 	"bufio"
 	"encoding/csv"
+	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
+	"log"
+	"math"
 	"regexp"
 	"strings"
 
@@ -39,6 +43,8 @@ func Parse(conf cfg.Config, input io.Reader) (Tabdata, error) {
 	// first step, parse the data
 	if len(conf.Separator) == 1 {
 		data, err = parseCSV(conf, input)
+	} else if conf.InputJSON {
+		data, err = parseJSON(conf, input)
 	} else {
 		data, err = parseTabular(conf, input)
 	}
@@ -60,6 +66,43 @@ func Parse(conf cfg.Config, input io.Reader) (Tabdata, error) {
 	return data, err
 }
 
+/*
+ * Setup headers,  given headers might  be usable headers or  just the
+ * first row, which we use to  determine how many headers to generate,
+ * if enabled.
+ */
+func SetHeaders(conf cfg.Config, headers []string) []string {
+	if !conf.AutoHeaders && len(conf.CustomHeaders) == 0 {
+		return headers
+	}
+
+	if conf.AutoHeaders {
+		heads := make([]string, len(headers))
+		for idx := range headers {
+			heads[idx] = fmt.Sprintf("%d", idx+1)
+		}
+
+		return heads
+	}
+
+	if len(conf.CustomHeaders) == len(headers) {
+		return conf.CustomHeaders
+	}
+
+	// use as much custom ones we have, generate the remainder
+	heads := make([]string, len(headers))
+
+	for idx := range headers {
+		if idx < len(conf.CustomHeaders) {
+			heads[idx] = conf.CustomHeaders[idx]
+		} else {
+			heads[idx] = fmt.Sprintf("%d", idx+1)
+		}
+	}
+
+	return heads
+}
+
 /*
 Parse CSV input.
 */
@@ -81,7 +124,7 @@ func parseCSV(conf cfg.Config, input io.Reader) (Tabdata, error) {
 	}
 
 	if len(records) >= 1 {
-		data.headers = records[0]
+		data.headers = SetHeaders(conf, records[0])
 		data.columns = len(records)
 
 		for _, head := range data.headers {
@@ -92,9 +135,14 @@ func parseCSV(conf cfg.Config, input io.Reader) (Tabdata, error) {
 			}
 		}
 
-		if len(records) > 1 {
-			data.entries = records[1:]
+		if len(records) >= 1 {
+			if conf.AutoHeaders || len(conf.CustomHeaders) > 0 {
+				data.entries = records
+			} else {
+				data.entries = records[1:]
+			}
 		}
+
 	}
 
 	return data, nil
@@ -122,7 +170,9 @@ func parseTabular(conf cfg.Config, input io.Reader) (Tabdata, error) {
 			data.columns = len(parts)
 
 			// process all header fields
-			for _, part := range parts {
+			firstrow := make([]string, len(parts))
+
+			for idx, part := range parts {
 				// register widest header field
 				headerlen := len(part)
 				if headerlen > data.maxwidthHeader {
@@ -130,11 +180,22 @@ func parseTabular(conf cfg.Config, input io.Reader) (Tabdata, error) {
 				}
 
 				// register fields data
-				data.headers = append(data.headers, strings.TrimSpace(part))
+				firstrow[idx] = strings.TrimSpace(part)
 
 				// done
 				hadFirst = true
 			}
+
+			data.headers = SetHeaders(conf, firstrow)
+
+			if conf.AutoHeaders || len(conf.CustomHeaders) > 0 {
+				// we do not use generated headers, consider as row
+				if matchPattern(conf, line) == conf.InvertMatch {
+					continue
+				}
+
+				data.entries = append(data.entries, firstrow)
+			}
 		} else {
 			// data processing
 			if matchPattern(conf, line) == conf.InvertMatch {
@@ -172,6 +233,137 @@ func parseTabular(conf cfg.Config, input io.Reader) (Tabdata, error) {
 	return data, nil
 }
 
+/*
+Parse JSON input.  We only support an array of  maps.
+*/
+func parseRawJSON(conf cfg.Config, input io.Reader) (Tabdata, error) {
+	dec := json.NewDecoder(input)
+	headers := []string{}
+	idxmap := map[string]int{}
+	data := [][]string{}
+	row := []string{}
+	iskey := true
+	haveheaders := false
+	var currentfield string
+	var idx int
+	var isjson bool
+
+	for {
+		t, err := dec.Token()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		switch val := t.(type) {
+		case string:
+			if iskey {
+				if !haveheaders {
+					// consider only the keys of the first item as headers
+					headers = append(headers, val)
+				}
+				currentfield = val
+			} else {
+				if !haveheaders {
+					// the first row uses the order as it comes in
+					row = append(row, val)
+				} else {
+					// use  the pre-determined  order, that  way items
+					// can be in any order as long as they contain all
+					// neccessary  fields. They may also  contain less
+					// fields than the  first item, these will contain
+					// the empty string
+					row[idxmap[currentfield]] = val
+				}
+			}
+
+		case float64:
+			var value string
+
+			// we set precision to 0 if the float is a whole number
+			if val == math.Trunc(val) {
+				value = fmt.Sprintf("%.f", val)
+			} else {
+				value = fmt.Sprintf("%f", val)
+			}
+
+			if !haveheaders {
+				row = append(row, value)
+			} else {
+				row[idxmap[currentfield]] = value
+			}
+
+		case nil:
+			// we ignore here if a value  shall be an int or a string,
+			// because tablizer only works with strings anyway
+			if !haveheaders {
+				row = append(row, "")
+			} else {
+				row[idxmap[currentfield]] = ""
+			}
+
+		case json.Delim:
+			if val.String() == "}" {
+				data = append(data, row)
+				row = make([]string, len(headers))
+				idx++
+
+				if !haveheaders {
+					// remember  the array position of  header fields,
+					// which we use to  assign elements to the correct
+					// row index
+					for i, header := range headers {
+						idxmap[header] = i
+					}
+				}
+
+				haveheaders = true
+			}
+			isjson = true
+		default:
+			fmt.Printf("unknown token: %v type: %T\n", t, t)
+		}
+
+		iskey = !iskey
+	}
+
+	if isjson && (len(headers) == 0 || len(data) == 0) {
+		return Tabdata{}, errors.New("failed to parse JSON, input did not contain array of hashes")
+	}
+
+	return Tabdata{headers: headers, entries: data, columns: len(headers)}, nil
+}
+
+func parseJSON(conf cfg.Config, input io.Reader) (Tabdata, error) {
+	// parse raw json
+	data, err := parseRawJSON(conf, input)
+	if err != nil {
+		return data, err
+	}
+
+	// apply filter, if any
+	filtered := [][]string{}
+	var line string
+
+	for _, row := range data.entries {
+		line = strings.Join(row, " ")
+
+		if matchPattern(conf, line) == conf.InvertMatch {
+			continue
+		}
+
+		filtered = append(filtered, row)
+	}
+
+	if len(filtered) != len(data.entries) {
+		data.entries = filtered
+	}
+
+	return data, nil
+}
+
 func PostProcess(conf cfg.Config, data *Tabdata) (*Tabdata, bool, error) {
 	var modified bool
 

lib/parser_test.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
@@ -19,10 +19,11 @@ package lib
 
 import (
 	"fmt"
-	"reflect"
+	"io"
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/tlinden/tablizer/cfg"
 )
 
@@ -33,7 +34,7 @@ var input = []struct {
 }{
 	{
 		name:      "tabular-data",
-		separator: cfg.DefaultSeparator,
+		separator: cfg.SeparatorTemplates[":default:"],
 		text: `
 ONE    TWO    THREE  
 asd    igig   cxxxncnc  
@@ -67,27 +68,21 @@ func TestParser(t *testing.T) {
 		t.Run(testname, func(t *testing.T) {
 			readFd := strings.NewReader(strings.TrimSpace(testdata.text))
 			conf := cfg.Config{Separator: testdata.separator}
-			gotdata, err := Parse(conf, readFd)
+			gotdata, err := wrapValidateParser(conf, readFd)
 
-			if err != nil {
-				t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)
-			}
-
-			if !reflect.DeepEqual(data, gotdata) {
-				t.Errorf("Parser returned invalid data\nExp: %+v\nGot: %+v\n",
-					data, gotdata)
-			}
+			assert.NoError(t, err)
+			assert.EqualValues(t, data, gotdata)
 		})
 	}
 }
 
 func TestParserPatternmatching(t *testing.T) {
 	var tests = []struct {
-		name     string
-		entries  [][]string
-		patterns []*cfg.Pattern
-		invert   bool
-		want     bool
+		name      string
+		entries   [][]string
+		patterns  []*cfg.Pattern
+		invert    bool
+		wanterror bool
 	}{
 		{
 			name: "match",
@@ -121,18 +116,13 @@ func TestParserPatternmatching(t *testing.T) {
 				_ = conf.PreparePattern(testdata.patterns)
 
 				readFd := strings.NewReader(strings.TrimSpace(inputdata.text))
-				gotdata, err := Parse(conf, readFd)
+				data, err := wrapValidateParser(conf, readFd)
 
-				if err != nil {
-					if !testdata.want {
-						t.Errorf("Parser returned error: %s\nData processed so far: %+v",
-							err, gotdata)
-					}
+				if testdata.wanterror {
+					assert.Error(t, err)
 				} else {
-					if !reflect.DeepEqual(testdata.entries, gotdata.entries) {
-						t.Errorf("Parser returned invalid data (pattern: %s, invert: %t)\nExp: %+v\nGot: %+v\n",
-							testdata.name, testdata.invert, testdata.entries, gotdata.entries)
-					}
+					assert.NoError(t, err)
+					assert.EqualValues(t, testdata.entries, data.entries)
 				}
 			})
 		}
@@ -158,15 +148,282 @@ asd    igig
 19191  EDD 1  X`
 
 	readFd := strings.NewReader(strings.TrimSpace(table))
-	conf := cfg.Config{Separator: cfg.DefaultSeparator}
-	gotdata, err := Parse(conf, readFd)
+	conf := cfg.Config{Separator: cfg.SeparatorTemplates[":default:"]}
+	gotdata, err := wrapValidateParser(conf, readFd)
 
-	if err != nil {
-		t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)
+	assert.NoError(t, err)
+	assert.EqualValues(t, data, gotdata)
+}
+
+func TestParserJSONInput(t *testing.T) {
+	var tests = []struct {
+		name      string
+		input     string
+		expect    Tabdata
+		wanterror bool // true: expect fail, false: expect success
+	}{
+		{
+			// too deep nesting
+			name:      "invalidjson",
+			wanterror: true,
+			input: `[
+  {
+    "item": {
+       "NAME": "postgres-operator-7f4c7c8485-ntlns",
+       "READY": "1/1",
+       "STATUS": "Running",
+       "RESTARTS": "0",
+       "AGE": "24h"
+    }
+  }
+`,
+			expect: Tabdata{},
+		},
+
+		{
+			// contains nil, int and float values
+			name:      "niljson",
+			wanterror: false,
+			input: `[
+  {
+    "NAME": "postgres-operator-7f4c7c8485-ntlns",
+    "READY": "1/1",
+    "STATUS": "Running",
+    "RESTARTS": 0,
+    "AGE": null,
+    "X": 12,
+    "Y": 34.222
+  }
+]`,
+			expect: Tabdata{
+				columns: 7,
+				headers: []string{"NAME", "READY", "STATUS", "RESTARTS", "AGE", "X", "Y"},
+				entries: [][]string{
+					[]string{
+						"postgres-operator-7f4c7c8485-ntlns",
+						"1/1",
+						"Running",
+						"0",
+						"",
+						"12",
+						"34.222000",
+					},
+				},
+			},
+		},
+
+		{
+			// one field missing + different order
+			// but shall not fail
+			name:      "kgpfail",
+			wanterror: false,
+			input: `[
+  {
+    "NAME": "postgres-operator-7f4c7c8485-ntlns",
+    "READY": "1/1",
+    "STATUS": "Running",
+    "RESTARTS": "0",
+    "AGE": "24h"
+  },
+  {
+    "NAME": "wal-g-exporter-778dcd95f5-wcjzn",
+    "RESTARTS": "0",
+    "READY": "1/1",
+    "AGE": "24h"
+  }
+]`,
+			expect: Tabdata{
+				columns: 5,
+				headers: []string{"NAME", "READY", "STATUS", "RESTARTS", "AGE"},
+				entries: [][]string{
+					[]string{
+						"postgres-operator-7f4c7c8485-ntlns",
+						"1/1",
+						"Running",
+						"0",
+						"24h",
+					},
+					[]string{
+						"wal-g-exporter-778dcd95f5-wcjzn",
+						"1/1",
+						"",
+						"0",
+						"24h",
+					},
+				},
+			},
+		},
+
+		{
+			name:      "kgp",
+			wanterror: false,
+			input: `[
+  {
+    "NAME": "postgres-operator-7f4c7c8485-ntlns",
+    "READY": "1/1",
+    "STATUS": "Running",
+    "RESTARTS": "0",
+    "AGE": "24h"
+  },
+  {
+    "NAME": "wal-g-exporter-778dcd95f5-wcjzn",
+    "STATUS": "Running",
+    "READY": "1/1",
+    "RESTARTS": "0",
+    "AGE": "24h"
+  }
+]`,
+			expect: Tabdata{
+				columns: 5,
+				headers: []string{"NAME", "READY", "STATUS", "RESTARTS", "AGE"},
+				entries: [][]string{
+					[]string{
+						"postgres-operator-7f4c7c8485-ntlns",
+						"1/1",
+						"Running",
+						"0",
+						"24h",
+					},
+					[]string{
+						"wal-g-exporter-778dcd95f5-wcjzn",
+						"1/1",
+						"Running",
+						"0",
+						"24h",
+					},
+				},
+			},
+		},
 	}
 
-	if !reflect.DeepEqual(data, gotdata) {
-		t.Errorf("Parser returned invalid data, Regex: %s\nExp: %+v\nGot: %+v\n",
-			conf.Separator, data, gotdata)
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("parse-json-%s", testdata.name)
+		t.Run(testname, func(t *testing.T) {
+			conf := cfg.Config{InputJSON: true}
+
+			readFd := strings.NewReader(strings.TrimSpace(testdata.input))
+			data, err := wrapValidateParser(conf, readFd)
+
+			if testdata.wanterror {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.EqualValues(t, testdata.expect, data)
+			}
+		})
 	}
 }
+
+func TestParserSeparators(t *testing.T) {
+	list := []string{"alpha", "beta", "delta"}
+
+	tests := []struct {
+		input string
+		sep   string
+	}{
+		{
+			input: `🎲`,
+			sep:   ":nonprint:",
+		},
+		{
+			input: `|`,
+			sep:   ":pipe:",
+		},
+		{
+			input: `   `,
+			sep:   ":spaces:",
+		},
+		{
+			input: "   \t  ",
+			sep:   ":tab:",
+		},
+		{
+			input: `-`,
+			sep:   ":nonword:",
+		},
+		{
+			input: `//$`,
+			sep:   ":special:",
+		},
+	}
+
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("parse-%s", testdata.sep)
+		t.Run(testname, func(t *testing.T) {
+			header := strings.Join(list, testdata.input)
+			row := header
+			content := header + "\n" + row
+
+			readFd := strings.NewReader(strings.TrimSpace(content))
+			conf := cfg.Config{Separator: testdata.sep}
+			conf.ApplyDefaults()
+
+			gotdata, err := wrapValidateParser(conf, readFd)
+
+			assert.NoError(t, err)
+			assert.EqualValues(t, [][]string{list}, gotdata.entries)
+		})
+	}
+}
+
+func TestParserSetHeaders(t *testing.T) {
+	row := []string{"c", "b", "c", "d", "e"}
+
+	tests := []struct {
+		name   string
+		custom []string
+		expect []string
+		auto   bool
+	}{
+		{
+			name:   "default",
+			expect: row,
+		},
+		{
+			name:   "auto",
+			expect: strings.Split("1 2 3 4 5", " "),
+			auto:   true,
+		},
+		{
+			name:   "custom-complete",
+			custom: strings.Split("A B C D E", " "),
+			expect: strings.Split("A B C D E", " "),
+		},
+		{
+			name:   "custom-too-short",
+			custom: strings.Split("A B", " "),
+			expect: strings.Split("A B 3 4 5", " "),
+		},
+		{
+			name:   "custom-too-long",
+			custom: strings.Split("A B C D E F G", " "),
+			expect: strings.Split("A B C D E", " "),
+		},
+	}
+
+	for _, testdata := range tests {
+		testname := fmt.Sprintf("parse-%s", testdata.name)
+		t.Run(testname, func(t *testing.T) {
+			conf := cfg.Config{
+				AutoHeaders:   testdata.auto,
+				CustomHeaders: testdata.custom,
+			}
+			headers := SetHeaders(conf, row)
+
+			assert.NotNil(t, headers)
+			assert.EqualValues(t, testdata.expect, headers)
+		})
+	}
+}
+
+func wrapValidateParser(conf cfg.Config, input io.Reader) (Tabdata, error) {
+	data, err := Parse(conf, input)
+
+	if err != nil {
+		return data, err
+	}
+
+	err = ValidateConsistency(&data)
+
+	return data, err
+}

lib/printer.go

@@ -19,6 +19,7 @@ package lib
 
 import (
 	"encoding/csv"
+	"encoding/json"
 	"fmt"
 	"io"
 	"log"
@@ -61,6 +62,8 @@ func printData(writer io.Writer, conf cfg.Config, data *Tabdata) {
 		printShellData(writer, data)
 	case cfg.Yaml:
 		printYamlData(writer, data)
+	case cfg.Json:
+		printJsonData(writer, data)
 	case cfg.CSV:
 		printCSVData(writer, conf, data)
 	default:
@@ -291,6 +294,35 @@ func printShellData(writer io.Writer, data *Tabdata) {
 	output(writer, out)
 }
 
+func printJsonData(writer io.Writer, data *Tabdata) {
+	objlist := make([]map[string]any, len(data.entries))
+
+	if len(data.entries) > 0 {
+		for i, entry := range data.entries {
+			obj := make(map[string]any, len(entry))
+
+			for idx, value := range entry {
+				num, err := strconv.Atoi(value)
+				if err == nil {
+					obj[data.headers[idx]] = num
+				} else {
+					obj[data.headers[idx]] = value
+				}
+			}
+
+			objlist[i] = obj
+		}
+	}
+
+	jsonstr, err := json.MarshalIndent(&objlist, "", "  ")
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	output(writer, string(jsonstr))
+}
+
 func printYamlData(writer io.Writer, data *Tabdata) {
 	type Data struct {
 		Entries []map[string]interface{} `yaml:"entries"`

lib/printer_test.go

@@ -23,6 +23,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/tlinden/tablizer/cfg"
 )
 
@@ -124,6 +125,31 @@ ceta,33d12h,9,06/Jan/2008 15:04:05 -0700`,
 NAME="beta" DURATION="1d10h5m1s" COUNT="33" WHEN="3/1/2014"
 NAME="alpha" DURATION="4h35m" COUNT="170" WHEN="2013-Feb-03"
 NAME="ceta" DURATION="33d12h" COUNT="9" WHEN="06/Jan/2008 15:04:05 -0700"`,
+	},
+	{
+		name:      "json",
+		mode:      cfg.Json,
+		numberize: false,
+		expect: `[
+  {
+    "COUNT": 33,
+    "DURATION": "1d10h5m1s",
+    "NAME": "beta",
+    "WHEN": "3/1/2014"
+  },
+  {
+    "COUNT": 170,
+    "DURATION": "4h35m",
+    "NAME": "alpha",
+    "WHEN": "2013-Feb-03"
+  },
+  {
+    "COUNT": 9,
+    "DURATION": "33d12h",
+    "NAME": "ceta",
+    "WHEN": "06/Jan/2008 15:04:05 -0700"
+  }
+]`,
 	},
 	{
 		name:      "yaml",
@@ -291,6 +317,7 @@ func TestPrinter(t *testing.T) {
 				conf.UseSortByColumn = []int{testdata.column}
 			}
 
+			conf.Separator = cfg.SeparatorTemplates[":default:"]
 			conf.ApplyDefaults()
 
 			// the test checks the len!
@@ -307,13 +334,7 @@ func TestPrinter(t *testing.T) {
 
 			got := strings.TrimSpace(writer.String())
 
-			if got != exp {
-				t.Errorf("not rendered correctly:\n+++ got:\n%s\n+++ want:\n%s",
-					got, exp,
-					// strings.ReplaceAll(got, " ", "_"),
-					// strings.ReplaceAll(exp, " ", "_")
-				)
-			}
+			assert.EqualValues(t, exp, got)
 		})
 	}
 }

lib/sort_test.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/tlinden/tablizer/cfg"
 )
 
@@ -41,9 +42,7 @@ func TestDuration2Seconds(t *testing.T) {
 		testname := fmt.Sprintf("duration-%s", testdata.dur)
 		t.Run(testname, func(t *testing.T) {
 			seconds := duration2int(testdata.dur)
-			if seconds != testdata.expect {
-				t.Errorf("got %d, want %d", seconds, testdata.expect)
-			}
+			assert.EqualValues(t, testdata.expect, seconds)
 		})
 	}
 }
@@ -74,9 +73,7 @@ func TestCompare(t *testing.T) {
 		t.Run(testname, func(t *testing.T) {
 			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)
-			}
+			assert.EqualValues(t, testdata.want, got)
 		})
 	}
 }

lib/yank_test.go

@@ -22,6 +22,7 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/tiagomelo/go-clipboard/clipboard"
 	"github.com/tlinden/tablizer/cfg"
 )
@@ -59,14 +60,9 @@ func DISABLED_TestYankColumns(t *testing.T) {
 			printData(&writer, conf, &data)
 
 			got, err := cb.PasteText()
-			if err != nil {
-				t.Errorf("failed to fetch yanked text from clipboard")
-			}
 
-			if got != testdata.expect {
-				t.Errorf("not yanked correctly:\n+++ got:\n%s\n+++ want:\n%s",
-					got, testdata.expect)
-			}
+			assert.NoError(t, err)
+			assert.EqualValues(t, testdata.expect, got)
 		})
 	}
 }

t/test-basics.txtar

@@ -1,7 +1,10 @@
 # usage
-exec tablizer -h
+exec tablizer --help
 stdout Usage
 
+exec tablizer -h
+stdout show
+
 # version
 exec tablizer -V
 stdout version

tablizer.1

@@ -133,7 +133,7 @@
 .\" ========================================================================
 .\"
 .IX Title "TABLIZER 1"
-.TH TABLIZER 1 "2025-09-30" "1" "User Commands"
+.TH TABLIZER 1 "2025-10-13" "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
@@ -152,13 +152,16 @@ tablizer \- Manipulate tabular output of other programs
 \&      \-n, \-\-numbering                    Enable header numbering
 \&      \-N, \-\-no\-color                     Disable pattern highlighting
 \&      \-H, \-\-no\-headers                   Disable headers display
-\&      \-s, \-\-separator <string>           Custom field separator
+\&      \-s, \-\-separator <string>           Custom field separator (maybe char, string or :class:)
 \&      \-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
+\&      \-j, \-\-json                         Read JSON input (must be array of hashes)
 \&      \-I, \-\-interactive                  Interactively filter and select rows
+\&      \-g, \-\-auto\-headers                 Generate headers if there are none present in input
+\&      \-x, \-\-custom\-headers a,b,...       Use custom headers, separated by comma
 \&
 \&    Output Flags (mutually exclusive):
 \&      \-X, \-\-extended                     Enable extended output
@@ -166,12 +169,13 @@ tablizer \- Manipulate tabular output of other programs
 \&      \-O, \-\-orgtbl                       Enable org\-mode table output
 \&      \-S, \-\-shell                        Enable shell evaluable output
 \&      \-Y, \-\-yaml                         Enable yaml output
+\&      \-J, \-\-jsonout                      Enable JSON output
 \&      \-C, \-\-csv                          Enable CSV output
 \&      \-A, \-\-ascii                        Default output mode, ascii tabular
 \&      \-L, \-\-hightlight\-lines             Use alternating background colors for tables
+\&      \-o, \-\-ofs <char>                   Output field separator, used by \-A and \-C. 
 \&      \-y, \-\-yank\-columns                 Yank specified columns (separated by ,) to clipboard,
 \&                                         space separated
-\&          \-\-ofs <char>                   Output field separator, used by \-A and \-C. 
 \&
 \&    Sort Mode Flags (mutually exclusive):
 \&      \-a, \-\-sort\-age                     sort according to age (duration) string
@@ -292,6 +296,62 @@ Sorts timestamps.
 .PP
 Finally the  \fB\-d\fR option  enables debugging  output which  is mostly
 useful for the developer.
+.SS "\s-1SEPARATOR\s0"
+.IX Subsection "SEPARATOR"
+The option \fB\-s\fR can be a single character, in which case the \s-1CSV\s0
+parser will be invoked. You can also specify a string as
+separator. The string will be interpreted as literal string unless it
+is a valid go regular expression. For example:
+.PP
+.Vb 1
+\&    \-s \*(Aq\et{2,}\e\*(Aq
+.Ve
+.PP
+is being used as a regexp and will match two or more consecutive tabs.
+.PP
+.Vb 1
+\&    \-s \*(Aqfoo\*(Aq
+.Ve
+.PP
+on the other hand is no regular expression and will be used literally.
+.PP
+To make live easier, there are a couple of predefined regular
+expressions, which you can specify as classes:
+.Sp
+.RS 4
+* 		:tab:
+.Sp
+Matches a tab and eats spaces around it.
+.Sp
+*		:spaces:
+.Sp
+Matches 2 or more spaces.
+.Sp
+*		:pipe:
+.Sp
+Matches a pipe character and eats spaces around it.
+.Sp
+*		:default:
+.Sp
+Matches 2 or more spaces or tab. This is the default separator if none
+is specified.
+.Sp
+*		:nonword:
+.Sp
+Matches a non-word character.
+.Sp
+*		:nondigit:
+.Sp
+Matches a non-digit character.
+.Sp
+*		:special:
+.Sp
+Matches one or more special chars like brackets, dollar sign, slashes etc.
+.Sp
+*		:nonprint:
+.Sp
+Matches one or more non-printable characters.
+.RE
 .SS "\s-1PATTERNS AND FILTERING\s0"
 .IX Subsection "PATTERNS AND FILTERING"
 You can reduce  the rows being displayed by using  one or more regular

tablizer.pod

@@ -13,13 +13,16 @@ tablizer - Manipulate tabular output of other programs
       -n, --numbering                    Enable header numbering
       -N, --no-color                     Disable pattern highlighting
       -H, --no-headers                   Disable headers display
-      -s, --separator <string>           Custom field separator
+      -s, --separator <string>           Custom field separator (maybe char, string or :class:)
       -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
+      -j, --json                         Read JSON input (must be array of hashes)
       -I, --interactive                  Interactively filter and select rows
+      -g, --auto-headers                 Generate headers if there are none present in input
+      -x, --custom-headers a,b,...       Use custom headers, separated by comma
 
     Output Flags (mutually exclusive):
       -X, --extended                     Enable extended output
@@ -27,12 +30,13 @@ tablizer - Manipulate tabular output of other programs
       -O, --orgtbl                       Enable org-mode table output
       -S, --shell                        Enable shell evaluable output
       -Y, --yaml                         Enable yaml output
+      -J, --jsonout                      Enable JSON output
       -C, --csv                          Enable CSV output
       -A, --ascii                        Default output mode, ascii tabular
       -L, --hightlight-lines             Use alternating background colors for tables
+      -o, --ofs <char>                   Output field separator, used by -A and -C. 
       -y, --yank-columns                 Yank specified columns (separated by ,) to clipboard,
                                          space separated
-          --ofs <char>                   Output field separator, used by -A and -C. 
 
     Sort Mode Flags (mutually exclusive):
       -a, --sort-age                     sort according to age (duration) string
@@ -152,6 +156,62 @@ Sorts timestamps.
 Finally the  B<-d> option  enables debugging  output which  is mostly
 useful for the developer.
 
+=head2 SEPARATOR
+
+The option B<-s> can be a single character, in which case the CSV
+parser will be invoked. You can also specify a string as
+separator. The string will be interpreted as literal string unless it
+is a valid go regular expression. For example:
+
+    -s '\t{2,}\'
+
+is being used as a regexp and will match two or more consecutive tabs.
+
+    -s 'foo'
+
+on the other hand is no regular expression and will be used literally.
+
+To make live easier, there are a couple of predefined regular
+expressions, which you can specify as classes:
+
+=over
+
+* 		:tab:      
+
+Matches a tab and eats spaces around it.
+
+*		:spaces:
+
+Matches 2 or more spaces.
+
+*		:pipe:
+
+Matches a pipe character and eats spaces around it.
+
+*		:default:
+
+Matches 2 or more spaces or tab. This is the default separator if none
+is specified.
+
+*		:nonword:
+
+Matches a non-word character.
+
+*		:nondigit:
+
+Matches a non-digit character.
+
+*		:special:
+
+Matches one or more special chars like brackets, dollar sign, slashes etc.
+
+*		:nonprint:
+
+Matches one or more non-printable characters.
+
+
+=back
+
 =head2 PATTERNS AND FILTERING
 
 You can reduce  the rows being displayed by using  one or more regular