Merge branch 'main' into feature/yank

cmd/tablizer.go

@@ -6,7 +6,7 @@ NAME
 
 SYNOPSIS
         Usage:
-          tablizer [regex] [file, ...] [flags]
+          tablizer [regex,...] [file, ...] [flags]
     
         Operational Flags:
           -c, --columns string              Only show the speficied columns (separated by ,)
@@ -17,7 +17,7 @@ SYNOPSIS
           -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
+          -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
 
@@ -132,30 +132,43 @@ DESCRIPTION
     for the developer.
 
   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: <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:
+    <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 search feature by providing the
+    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.
 
@@ -170,6 +183,10 @@ DESCRIPTION
     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
@@ -406,7 +423,7 @@ AUTHORS
 var usage = `
 
 Usage:
-  tablizer [regex] [file, ...] [flags]
+  tablizer [regex,...] [file, ...] [flags]
 
 Operational Flags:
   -c, --columns string              Only show the speficied columns (separated by ,)
@@ -417,7 +434,7 @@ Operational Flags:
   -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
+  -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