Paint manages terminal colors and effects for you. It combines the strengths of gems like term-ansicolor or rainbow into a simple to use and flexible colorizer.
-
No string extensions (suitable for library development)
-
Supports setting 256 colors (for capable terminals)
-
Supports setting any effects (although most terminals won’t support it)
-
Simple to use
-
Custom shortcuts can be defined and flexibly mixed in
-
Fall-back modes for non-256-color terminals (Paint.mode), supported modes:
-
256 colors
-
16 colors (only ansi colors, combined with bright effect)
-
8 colors (only ansi colors)
-
0 colors (deactivate)
-
Install with:
gem install paint
In Ruby do:
require 'paint'
The only method you need to know to get started is: Paint.[]
The first argument given to Paint.[] is the string to colorize (if the object is not a string, to_s will be called on the object). The other arguments describe how to modify/colorize the string. Let’s learn by example:
Paint['Ruby', :red] # sets ansi color red Paint['Ruby', :red, :bright] # also applies bright/bold effect Paint['Ruby', :bright, :red] # does the same as above Paint['Ruby', :red, :bright, :underline] # effects can often be combined Paint['Ruby', :red, :blue] # the second color you define is for background Paint['Ruby', nil, :blue] # pass a nil before a color to ignore foreground and only set background color Paint['Ruby', [100, 255, 5]] # you can define rgb colors that map to one of 256 colors. Only supported on 256-color terminals, of course Paint['Ruby', "gold", "snow"] # Paint supports rgb.txt color names, note that the arguments are strings (:yellow != "yellow")! Paint['Ruby', "#123456"] # html like definitions are possible. Paint['Ruby', "fff"] # another html hex definition Paint['Ruby', :random] # pass :random to get one of eight random ansi foreground colors Paint['Ruby', :inverse] # swaps fore- and background Paint['Ruby', :italic, :encircle, :rapid_blink, :overline] # probably not supported effects Paint['Ruby'] # don't pass any argument and the string will not be changed
If you pass multiple colors, the first one is taken as foreground color and the second one defines the background color (all others will be ignored). To only change the background color, you have to pass a nil first. Effects can be passed in any order.
To see more examples, checkout the specs.
Terminal colors/effects are set by ansi escape sequences. These are strings that look like this: \e[X;X;X;X;X]m where X are integers with some meaning. For example, 0 means reset, 31 means red foreground and 41 red background. When you tell Paint to use one of the eight ansi base colors as foreground color, it just inserts a number between 30 and 37 in the sequence. The following colors are available:
:black, :red, :green, :yellow, :blue, :magenta, :cyan, :white, (:default)
When combined with the :bright (= :bold) effect, the color in the terminal emulator often differs a little bit.
Through special sequences it’s also possible to set 256-colors, instead of 8, which is also supported by many - but not all - terminals. Paint automatically translates given rgb colors to a suitable color of the 256 available colors.
When using the Paint.[] method, Paint wraps the given string between the calculated escape sequence and an reset sequence ("\e[0m"). You can directly get only the escape sequence by using the Paint.color method.
Also see en.wikipedia.org/wiki/ANSI_escape_code:
0) :reset, :nothing 1) :bright, :bold 4) :underline 7) :inverse, :negative 8) :conceal, :hide 22) :clean 24) :underline_off 26) :inverse_off, :positive 27) :conceal_off, :show, :reveal
2) :faint 3) :italic 5) :blink, :slow_blink 6) :rapid_blink 9) :crossed, :crossed_out 10) :default_font, :font0 11-19) :font1, :font2, :font3, :font4, :font5, :font6, :font7, :font8, :font9 20) :fraktur 21) :bright_off, :bold_off, :double_underline 23) :italic_off, :fraktur_off 25) :blink_off 29) :crossed_off, :crossed_out_off 51) :frame 52) :encircle 53) :overline 54) :frame_off, :encircle_off 55) :overline_off
You can choose between three ways to use Paint.[] by setting Paint.mode to one of the following:
-
256: full support
-
16: don’t use 256 colors, but the ansi eight ones (combined with bright effect)
-
8: don’t use 256 colors, but the ansi eight ones
-
0: don’t colorize at all
Paint tries to detect automatically the proper value, but this is still experimental. Please open an issue if Paint.detect_mode yields a wrong value for you.
Now for the fancy part: Color shortcuts for your gems and scripts! Note: You don’t have to use them (and only stick to Paint.[]) ;)
It’s easy: Just setup a hash of symbol keys and escape string values at: Paint::SHORTCUTS[:your_namespace]. They are stored directly as escape sequences for performance reasons (this also means, you need different namespaces for different Paint.modes). Example:
Paint::SHORTCUTS[:example] = { :white => Paint.color(:black), :red => Paint.color(:red, :bright), :title => Paint.color(:underline), }
The methods become rubymagically available in a Paint child model (via method_missing):
Paint::Example.red 'Ruby' # => "\e[31;1mRuby\e[0m" Paint::Example.white # => "\e[37m"
As you can see, the helper methods look useful and can take either one (wrap string) or none (only color) arguments …but they aren’t really short yet.
Just include them:
include Paint::Example red # => "\e[31;1m" white 'Ruby' # => "\e[30m"
All shortcuts, defined in your shortcut namespace at this time, are now (privately) available in your current namespace (without using a method_missing implementation).
Furthermore, there are two variations of this approach:
include Paint::Example::String "Ruby".title # => "\e[4mRuby\e[0m" 5.red # => "\e[31;1m5\e[0m"
In this case, self will be converted to a string and wrapped with the specific color code. Note, that the helper methods doesn’t take any arguments when using this method.
The third way allows you to get a single color helper method to avoid cluttering namespaces:
include Paint::Example::Prefix::ExampleName "Ruby".example_name(:red) # => "\e[31;1mRuby\e[0m"
There are some helper methods available. You can get a p like alternative for calling Paint.[]:
require 'paint/pa' pa "Ruby", :red, :underline # same as puts Paint["Ruby", :red, :underline]
Another one is Paint.unpaint, which removes any ansi colors:
Paint.unpaint( Paint['J-_-L', :red, :bright] ).should == 'J-_-L'
-
24-bit color support (konsole), see www.reddit.com/r/programming/comments/6gxnp/making_the_most_of_colour_on_text_consoles/c03t8k8
Mainly influenced by rainbow and term-ansicolor.
Copyright © 2011 Jan Lelis, rbjl.net, released under the MIT license.
Contributions by and thanks to:
J-_-L