Module: Vedeu::EscapeSequences::Colours

Extended by:
Colours
Included in:
Vedeu::Esc, Colours
Defined in:
lib/vedeu/esc/colours.rb

Overview

Provides colour related escape sequences.

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.background_codes ⇒ Hash<Symbol => Fixnum>

Produces the background named colour escape sequence hash from the foreground escape sequence hash.

Returns:

  • (Hash<Symbol => Fixnum>) 


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# File 'lib/vedeu/esc/colours.rb', line 17

def background_codes
  hash = {}
  foreground_codes.inject(hash) do |h, (k, v)|
    h.merge!(k => v + 10)
  end
end

.define_backgrounds! ⇒ void (private)

This method returns an undefined value.



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# File 'lib/vedeu/esc/colours.rb', line 78

def define_backgrounds!
  background_codes.each do |key, code|
    define_method('on_' + key.to_s) do |&blk|
      "\e[#{code}m" + (blk ? blk.call + "\e[49m" : '')
    end
  end
end

.define_foregrounds! ⇒ void (private)

This method returns an undefined value.

Dynamically creates methods for each terminal named colour. When a block is given, then the colour is reset to ‘default’ once the block is called.



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# File 'lib/vedeu/esc/colours.rb', line 91

def define_foregrounds!
  foreground_codes.each do |key, code|
    define_method(key) do |&blk|
      "\e[#{code}m" + (blk ? blk.call + "\e[39m" : '')
    end
  end
end

.foreground_codes ⇒ Hash<Symbol => Fixnum> Also known as: codes

Produces the foreground named colour escape sequence hash. The background escape sequences are also generated from this by adding 10 to the values. This hash gives rise to methods you can call directly on ‘Esc` to produce the desired colours:

Examples:

Esc.red                     # => "\e[31m"

Esc.red { 'some text' }     # => "\e[31msome text\e[39m"

Esc.on_blue                 # => "\e[44m"

Esc.on_blue { 'some text' } # => "\e[44msome text\e[49m"

# Valid names:
:black, :red, :green, :yellow, :blue, :magenta, :cyan,
:light_grey, :default, :dark_grey, :light_red, :light_green,
:light_yellow, :light_blue, :light_magenta, :light_cyan,
:white

Returns:

  • (Hash<Symbol => Fixnum>) 


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# File 'lib/vedeu/esc/colours.rb', line 46

def foreground_codes
  {
    black:         30,
    red:           31,
    green:         32,
    yellow:        33,
    blue:          34,
    magenta:       35,
    cyan:          36,
    light_grey:    37,
    default:       39,
    dark_grey:     90,
    light_red:     91,
    light_green:   92,
    light_yellow:  93,
    light_blue:    94,
    light_magenta: 95,
    light_cyan:    96,
    white:         97,
  }
end

.setup! ⇒ void

This method returns an undefined value.



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# File 'lib/vedeu/esc/colours.rb', line 70

def setup!
  define_backgrounds!
  define_foregrounds!
end

Instance Method Details

#background_codes ⇒ Hash<Symbol => Fixnum>

Produces the background named colour escape sequence hash from the foreground escape sequence hash.

Returns:

  • (Hash<Symbol => Fixnum>) 


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# File 'lib/vedeu/esc/colours.rb', line 17

def background_codes
  hash = {}
  foreground_codes.inject(hash) do |h, (k, v)|
    h.merge!(k => v + 10)
  end
end

#define_backgrounds! ⇒ void (private)

This method returns an undefined value.



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# File 'lib/vedeu/esc/colours.rb', line 78

def define_backgrounds!
  background_codes.each do |key, code|
    define_method('on_' + key.to_s) do |&blk|
      "\e[#{code}m" + (blk ? blk.call + "\e[49m" : '')
    end
  end
end

#define_foregrounds! ⇒ void (private)

This method returns an undefined value.

Dynamically creates methods for each terminal named colour. When a block is given, then the colour is reset to ‘default’ once the block is called.



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# File 'lib/vedeu/esc/colours.rb', line 91

def define_foregrounds!
  foreground_codes.each do |key, code|
    define_method(key) do |&blk|
      "\e[#{code}m" + (blk ? blk.call + "\e[39m" : '')
    end
  end
end

#foreground_codes ⇒ Hash<Symbol => Fixnum> Also known as: codes

Produces the foreground named colour escape sequence hash. The background escape sequences are also generated from this by adding 10 to the values. This hash gives rise to methods you can call directly on ‘Esc` to produce the desired colours:

Examples:

Esc.red                     # => "\e[31m"

Esc.red { 'some text' }     # => "\e[31msome text\e[39m"

Esc.on_blue                 # => "\e[44m"

Esc.on_blue { 'some text' } # => "\e[44msome text\e[49m"

# Valid names:
:black, :red, :green, :yellow, :blue, :magenta, :cyan,
:light_grey, :default, :dark_grey, :light_red, :light_green,
:light_yellow, :light_blue, :light_magenta, :light_cyan,
:white

Returns:

  • (Hash<Symbol => Fixnum>) 


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# File 'lib/vedeu/esc/colours.rb', line 46

def foreground_codes
  {
    black:         30,
    red:           31,
    green:         32,
    yellow:        33,
    blue:          34,
    magenta:       35,
    cyan:          36,
    light_grey:    37,
    default:       39,
    dark_grey:     90,
    light_red:     91,
    light_green:   92,
    light_yellow:  93,
    light_blue:    94,
    light_magenta: 95,
    light_cyan:    96,
    white:         97,
  }
end

#setup! ⇒ void

This method returns an undefined value.



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# File 'lib/vedeu/esc/colours.rb', line 70

def setup!
  define_backgrounds!
  define_foregrounds!
end