ターミナルで”Google”をカラー表示

まず、ANSIColor.pmを作る。

package ANSIColor;

use strict;
use warnings;
use base 'Exporter';

use constant {
    # foreground color
    BLACK  => "\033[30m",
    RED    => "\033[31m",
    GREEN  => "\033[32m",
    YELLOW => "\033[33m",
    BLUE   => "\033[34m",
    PURPLE => "\033[35m",
    CYAN   => "\033[36m",
    WHITE  => "\033[37m",

    # background color
    BLACKB  => "\033[40m",
    REDB    => "\033[41m",
    GREENB  => "\033[42m",
    YELLOWB => "\033[43m",
    BLUEB   => "\033[44m",
    PURPLEB => "\033[45m",
    CYANB   => "\033[46m",
    WHITEB  => "\033[47m",

    # bold
    B => "\033[1m",
    BOFF => "\033[22m",

   # italics
    I => "\033[3m",
    IOFF => "\033[23m",

    # underline
    U => "\033[4m",
    UOFF => "\033[24m",

    # invert
    R => "\033[7m",
    ROFF => "\033[27m",

    # reset
    RESET  => "\033[0m",
};

our %EXPORT_TAGS = ('foreground' => [qw(BLACK RED GREEN YELLOW BLUE PURPLE CYAN WHITE RESET)],
                    'background' => [qw(BLACKB REDB GREENB YELLOWB BLUEB PURPLEB CYANB WHITEB RESET)],
                    'italic' => [qw(I ITON ITALIC ITALICON IOFF ITALICOFF RESET)],
                    'bold' => [qw(B BOLD BOLDON BOLDOFF BOFF RESET)],
                    'invert' => [qw(R INVON ROFF INVOFF)],
                    'underline' => [qw(U UL ULON UNDERLINE UNDERLINEON UOFF UNDERLINEOFF ULOFF)],
                );
$EXPORT_TAGS{'all'} = [map {@{$_}} values %EXPORT_TAGS];

our @EXPORT_OK = @{$EXPORT_TAGS{'all'}};

1;

あとは、以下を実行

>perl -e 'use ANSIColor qw(:foreground); print BLUE,G,RED,o,YELLOW,o,BLUE,g,GREEN,l,RED,e,RESET,"\n"'
Google

ターミナルがカラフルだと楽しくなります。

正規表現で使いたい場合は、eオプションを付けて、

use ANSIColor qw(:foreground);

# Wikipediaのgoogle項目冒頭 (http://en.wikipedia.org/wiki/Google) 
my $str =<<_EOS_;
Google Inc. is an American public corporation, earning revenue from 
advertising related to its Internet search, e-mail, online mapping, 
office productivity, social networking, and video sharing services 
as well as selling advertising-free versions of the same technologies. 
The Google headquarters, the Googleplex, is located in Mountain View, 
California. As of March 31, 2009, the company has 20,164 full-time employees.
_EOS_

$str =~ s/Google/BLUE.G.RED.o.YELLOW.o.BLUE.g.GREEN.l.RED.e.RESET/eg;
print $str;

結果は、

Google Inc. is an American public corporation, earning revenue from 
advertising related to its Internet search, e-mail, online mapping, 
office productivity, social networking, and video sharing services 
as well as selling advertising-free versions of the same technologies. 
The Google headquarters, the Googleplex, is located in Mountain View, 
California. As of March 31, 2009, the company has 20,164 full-time employees.