colorer

Easy ANSI code coloring for strings.

Synopsis

require 'colorer'
Colorer.def_basic_styles
Colorer.def_custom_styles :errorize => [ :red, :bold, :underline ],
                          :mysgr => [ :red, 8 ]

"a red bold underlined text on white background".red.bold.underline.onwhite
"an error string".errorize
"my native (Select Graphic Rendition) string".mysgr

'    reversed    '.reversed.or('==== reversed ====')

Colorer.def_strip_ansi
plain_text = colored_string.strip_ansi

Feedback!!!

This is feedback-driven software. Just send me a line about you and/or what you think about IRT: that will be a wonderful contribution that will help me to keep improving (and documenting) this software.

My email address is ddnexus at gmail.com … waiting for your. Ciao.

Features

Does not pollute String of unwanted methods
Allows you to define basic styles with one line of code
Allows you to easily add your own custom styles
Allows extended (Select Graphic Rendition) parameters

Basic Styles

You can define the basic styles for any string by using the def_basic_styles method:

# all basic styles
Colorer.def_basic_styles
"a string".green.bold.reversed.underline...

# a few basic styles
Colorer.define_styles [:bold, :reversed]
"a string".bold.reversed

# one basic style
Colorer.define_styles :red
"a string".red

Basic Styles List

clear
bold
underline
blinking
reversed
black
red
green
yellow
blue
magenta
cyan
white
onblack
onred
ongreen
onyellow
onblue
onmagenta
oncyan
onwhite

Custom Styles

You can define your own custom styles by aggregating any basic styles names:

Colorer.def_custom_styles :errorize => [ :red, :bold, :underline ],
                          :okize => [ :green, :bold ],
                          :crazyize => [ :magenta, :onyellow, :bold, :underline ]

error_string.errorize
# same as
error_string.red.bold.underline
ok_string.okeyze
# same as
ok_string.green.bold
crazy_string.crazyize
# same as
crazy_string.magenta.onyellow.bold.underline

SGR Styles

You can also add native SGR (Select Graphic Rendition) parameters (0..109) to any style:

Colorer.def_custom_styles :mysgr => [ :red, 8 ]

See en.wikipedia.org/wiki/ANSI_colors for a complete list

Strict ANSI

Some terminals don’t parse composite SGR styles correctly, and need separate SGR for each.

puts "\e[7;31;46mSTRING\e[0m"         # strict_ansi == true (may be difficult to parse)
puts "\e[7m\e[31m\e[46mSTRING\e[0m"   # strict_ansi == false

On the other way most of the terminals that parse them correctly can parse also separate SGRs, so Colorer will output non strict ansi by default. If you want to have strict ansi you can do:

Colorer.strict_ansi = true

or you can set the COLORER_ANSI_STRICT environment variable for a system wide setting.

Color

The color is true by defealut on a non-dumb tty terminal, anyway you can force it by explicitly setting it:

Colorer.color?         #=> true/false by default depending on your terminal
Colorer.color = true   # force true
Colorer.color?         #=> true
Colorer.color = false  # force false
Colorer.color?         #=> false