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Module Version: 0.16   Source  


Text::ANSI::Util - Routines for text containing ANSI escape codes


This document describes version 0.16 of Text::ANSI::Util (from Perl distribution Text-ANSI-Util), released on 2015-01-03.


 use Text::ANSI::Util qw(
     ta_detect ta_highlight ta_highlight_all ta_length ta_mbpad ta_mbswidth
     ta_mbswidth_height ta_mbwrap ta_pad ta_split_codes ta_split_codes_single
     ta_strip ta_wrap);

 # detect whether text has ANSI escape codes?
 say ta_detect("red");       # => false
 say ta_detect("\e[31mred"); # => true

 # calculate length of text (excluding the ANSI escape codes)
 say ta_length("red");       # => 3
 say ta_length("\e[31mred"); # => 3

 # calculate visual width of text if printed on terminal (can handle Unicode
 # wide characters and exclude the ANSI escape codes)
 say ta_mbswidth("\e[31mred");  # => 3
 say ta_mbswidth("\e[31m红色"); # => 4

 # ditto, but also return the number of lines
 say ta_mbswidth_height("\e[31mred\n红色"); # => [4, 2]

 # strip ANSI escape codes
 say ta_strip("\e[31mred"); # => "red"

 # split codes (ANSI codes are always on the even positions)
 my @parts = ta_split_codes("\e[31mred"); # => ("", "\e[31m", "red")

 # wrap text to a certain column width, handle ANSI escape codes
 say ta_wrap("....", 40);

 # ditto, but handle wide characters
 say ta_mbwrap(...);

 # pad (left, right, center) text to a certain width
 say ta_pad("foo", 10);                          # => "foo       "
 say ta_pad("foo", 10, "left");                  # => "       foo"
 say ta_pad("foo\nbarbaz\n", 10, "center", "."); # => "\n..barbaz..\n"

 # ditto, but handle wide characters
 say ta_mbpad(...);

 # truncate text to a certain width while still passing ANSI escape codes
 use Term::ANSIColor;
 my $text = color("red")."red text".color("reset"); # => "\e[31mred text\e[0m"
 say ta_trunc($text, 5);                            # => "\e[31mred t\e[0m"

 # ditto, but handle wide characters
 say ta_mbtrunc(...);

 # highlight the first occurence of some string within text
 say ta_highlight("some text", "ome", "\e[7m\e[31m");

 # ditto, but highlight all occurrences
 say ta_highlight_all(...);


This module provides routines for dealing with text containing ANSI escape codes (mainly ANSI color codes).

Current caveats:


ta_detect($text) => BOOL

Return true if $text contains ANSI escape codes, false otherwise.

ta_length($text) => INT

Count the number of characters in $text, while ignoring ANSI escape codes. Equivalent to length(ta_strip($text)). See also: ta_mbswidth().

ta_length_height($text) => [INT, INT]

Like ta_length(), but also gives height (number of lines). For example, ta_length_height("foobar\nb\n") gives [6, 3].

ta_mbswidth($text) => INT

Return visual width of $text (in number of columns) if printed on terminal. Equivalent to Text::WideChar::Util::mbswidth(ta_strip($text)). This function can be used e.g. in making sure that your text aligns vertically when output to the terminal in tabular/table format.

Note that ta_mbswidth() handles multiline text correctly, e.g.: ta_mbswidth("foo\nbarbaz") gives 6 instead of 3-1+8 = 8. It splits the input text first against /\r?\n/.

ta_mbswidth_height($text) => [INT, INT]

Like ta_mbswidth(), but also gives height (number of lines). For example, ta_mbswidth_height("西爪哇\nb\n") gives [6, 3].

ta_strip($text) => STR

Strip ANSI escape codes from $text, returning the stripped text.

ta_extract_codes($text) => STR

This is the opposite of ta_strip(), return only the ANSI codes in $text.

ta_split_codes($text) => LIST

Split $text to a list containing alternating ANSI escape codes and text. ANSI escape codes are always on the second element, fourth, and so on. Example:

 ta_split_codes("");              # => ()
 ta_split_codes("a");             # => ("a")
 ta_split_codes("a\e[31m");       # => ("a", "\e[31m")
 ta_split_codes("\e[31ma");       # => ("", "\e[31m", "a")
 ta_split_codes("\e[31ma\e[0m");  # => ("", "\e[31m", "a", "\e[0m")
 ta_split_codes("\e[31ma\e[0mb"); # => ("", "\e[31m", "a", "\e[0m", "b")
 ta_split_codes("\e[31m\e[0mb");  # => ("", "\e[31m\e[0m", "b")

so you can do something like:

 my @parts = ta_split_codes($text);
 while (my ($text, $ansicode) = splice(@parts, 0, 2)) {

ta_split_codes_single($text) => LIST

Like ta_split_codes() but each ANSI escape code is split separately, instead of grouped together. This routine is currently used internally e.g. for ta_mbwrap() and ta_highlight() to trace color reset/replay codes.

ta_wrap($text, $width, \%opts) => STR

Like Text::WideChar::Util's wrap() except handles ANSI escape codes. Perform color reset at the end of each line and a color replay at the start of subsequent line so the text is safe for combining in a multicolumn/tabular layout.


Performance: ~500/s on my Core i5 1.7GHz laptop for a ~1KB of text (with zero to moderate amount of color codes). As a comparison, Text::WideChar::Util's wrap() can do about 2000/s.

ta_mbwrap($text, $width, \%opts) => STR

Like ta_wrap(), but it uses ta_mbswidth() instead of ta_length(), so it can handle wide characters.

Performance: ~300/s on my Core i5 1.7GHz laptop for a ~1KB of text (with zero to moderate amount of color codes). As a comparison, Text::WideChar::Util's mbwrap() can do about 650/s.

ta_add_color_resets(@text) => LIST

Make sure that a color reset command (add \e[0m) to the end of each element and a replay of all the color codes from the previous element, from the last color reset) to the start of the next element, and so on. Return the new list.

This makes each element safe to be combined with other array of text into a single line, e.g. in a multicolumn/tabular layout. An example:

Without color resets:

 my @col1 = split /\n/, "\e[31mred\nmerah\e[0m";
 my @col2 = split /\n/, "\e[32mgreen\e[1m\nhijau tebal\e[0m";

 printf "%s | %s\n", $col1[0], $col2[0];
 printf "%s | %s\n", $col1[1], $col2[1];

the printed output:

 \e[31mred | \e[32mgreen
 merah\e[0m | \e[1mhijau tebal\e[0m

The merah text on the second line will become green because of the effect of the last color command printed (\e[32m). However, with ta_add_color_resets():

 my @col1 = ta_add_color_resets(split /\n/, "\e[31mred\nmerah\e[0m");
 my @col2 = ta_add_color_resets(split /\n/, "\e[32mgreen\e[1m\nhijau tebal\e[0m");

 printf "%s | %s\n", $col1[0], $col2[0];
 printf "%s | %s\n", $col1[1], $col2[1];

the printed output (<...>) marks the code added by ta_add_color_resets():

 \e[31mred<\e[0m> | \e[32mgreen\e[1m<\e[0m>
 <\e[31m>merah\e[0m | <\e[32m\e[1m>hijau tebal\e[0m

All the cells are printed with the intended colors.

ta_pad($text, $width[, $which[, $padchar[, $truncate]]]) => STR

Return $text padded with $padchar to $width columns. $which is either "r" or "right" for padding on the right (the default if not specified), "l" or "left" for padding on the right, or "c" or "center" or "centre" for left+right padding to center the text.

$padchar is whitespace if not specified. It should be string having the width of 1 column.

Does *not* handle multiline text; you can split text by /\r?\n/ yourself.

ta_mbpad($text, $width[, $which[, $padchar[, $truncate]]]) => STR

Like ta_pad() but it uses ta_mbswidth() instead of ta_length(), so it can handle wide characters.

ta_trunc($text, $width) => STR

Truncate $text to $width columns while still including all the ANSI escape codes. This ensures that truncated text still reset colors, etc.

Does *not* handle multiline text; you can split text by /\r?\n/ yourself.

ta_mbtrunc($text, $width) => STR

Like ta_trunc() but it uses ta_mbswidth() instead of ta_length(), so it can handle wide characters.

ta_highlight($text, $needle, $color) => STR

Highlight the first occurence of $needle in $text with <$color>, taking care not to mess up existing colors.

$needle can be a string or a Regexp object.

Implementation note: to not mess up colors, we save up all color codes from the last reset (\e[0m) before inserting the highlight color + highlight text. Then we issue \e[0m and the saved up color code to return back to the color state before the highlight is inserted. This is the same technique as described in ta_add_color_resets().

ta_highlight_all($text, $needle, $color) => STR

Like ta_highlight(), but highlight all occurences instead of only the first.


How do I truncate string based on number of characters?

You can simply use ta_trunc() even on text containing wide characters. ta_trunc() uses Perl's length() which works on a per-character basis.

How do I highlight a string case-insensitively?

You can currently use a regex for the $needle and use the i modifier. Example:

 use Term::ANSIColor;
 ta_highlight($text, qr/\b(foo)\b/i, color("bold red"));



Text::ANSITable uses this module. In fact, this module was first created specifically for Text::ANSITable.


Please visit the project's homepage at


Source repository is at


Please report any bugs or feature requests on the bugtracker website

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.


perlancar <>


This software is copyright (c) 2015 by

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

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