module Colorize
Overview
With Colorize you can change the fore- and background colors and text decorations when rendering text
on terminals supporting ANSI escape codes. It adds the colorize
method to Object
and thus all classes
as its main interface, which calls to_s
and surrounds it with the necessary escape codes
when it comes to obtaining a string representation of the object.
Its first argument changes the foreground color:
require "colorize"
"foo".colorize(:green)
100.colorize(:red)
[1, 2, 3].colorize(:blue)
There are alternative ways to change the foreground color:
require "colorize"
"foo".colorize.fore(:green)
"foo".colorize.green
To change the background color, the following methods are available:
require "colorize"
"foo".colorize.back(:green)
"foo".colorize.on(:green)
"foo".colorize.on_green
You can also pass an RGB color to colorize
:
require "colorize"
"foo".colorize(Colorize::ColorRGB.new(0, 255, 255)) # => "foo" in aqua
Or an 8-bit color:
require "colorize"
"foo".colorize(Colorize::Color256.new(208)) # => "foo" in orange
It's also possible to change the text decoration:
require "colorize"
"foo".colorize.mode(:underline)
"foo".colorize.underline
The colorize
method returns a Colorize::Object
instance,
which allows chaining methods together:
require "colorize"
"foo".colorize.fore(:yellow).back(:blue).mode(:underline)
With the toggle
method you can temporarily disable adding the escape codes.
Settings of the instance are preserved however and can be turned back on later:
require "colorize"
"foo".colorize(:red).toggle(false) # => "foo" without color
"foo".colorize(:red).toggle(false).toggle(true) # => "foo" in red
The color :default
will just leave the object as it is (but it's an Colorize::Object(String)
then).
That's handy in for example conditions:
require "colorize"
"foo".colorize(some_bool ? :green : :default)
Available colors are:
:default
:black
:red
:green
:yellow
:blue
:magenta
:cyan
:light_gray
:dark_gray
:light_red
:light_green
:light_yellow
:light_blue
:light_magenta
:light_cyan
:white
Available text decorations are:
:bold
:bright
:dim
:underline
:blink
:reverse
:hidden
Defined in:
colorize.cr:110colorize.cr:162
Class Method Summary
-
.enabled=(enabled : Bool)
If this value is
true
,Colorize::Object
is enabled by default. -
.enabled? : Bool
If this value is
true
,Colorize::Object
is enabled by default. -
.on_tty_only!
Makes
Colorize.enabled
true
if and only if both ofSTDOUT.tty?
andSTDERR.tty?
aretrue
and the tty is not considered a dumb terminal. - .reset(io = STDOUT)
Class Method Detail
If this value is true
, Colorize::Object
is enabled by default.
But if this value is false
, Colorize::Object
is disabled.
The default value is true
.
require "colorize"
Colorize.enabled = true
"hello".colorize.red.to_s # => "\e[31mhello\e[0m"
Colorize.enabled = false
"hello".colorize.red.to_s # => "hello"
If this value is true
, Colorize::Object
is enabled by default.
But if this value is false
, Colorize::Object
is disabled.
The default value is true
.
require "colorize"
Colorize.enabled = true
"hello".colorize.red.to_s # => "\e[31mhello\e[0m"
Colorize.enabled = false
"hello".colorize.red.to_s # => "hello"
Makes Colorize.enabled
true
if and only if both of STDOUT.tty?
and STDERR.tty?
are true
and the tty is not considered a dumb terminal.
This is determined by the environment variable called TERM
.
If TERM=dumb
, color won't be enabled.