Module: Sass::Callbacks

Defined in:: /var/www/sass-pages/.haml/lib/sass/callbacks.rb

Overview

A lightweight infrastructure for defining and running callbacks. Callbacks are defined using #define_callback at the class level, and called using run_#{name} at the instance level.

Clients can add callbacks by calling the generated on_#{name} method, and passing in a block that’s run when the callback is activated.

Examples:

Define a callback

class Munger
  extend Sass::Callbacks
  define_callback :string_munged

  def munge(str)
    res = str.gsub(/[a-z]/, '\1\1')
    run_string_munged str, res
    res
  end
end

Use a callback

m = Munger.new
m.on_string_munged {|str, res| puts "#{str} was munged into #{res}!"}
m.munge "bar" #=> bar was munged into bbaarr!

Instance Method Summary

- define_callback(name) protected Define a callback with the given name.

Instance Method Details

- define_callback(name) (protected)

This method returns an undefined value.

Define a callback with the given name. This will define an on_#{name} method that registers a block, and a run_#{name} method that runs that block (optionall with some arguments).

Parameters:

(Symbol) name — The name of the callback



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# File '/var/www/sass-pages/.haml/lib/sass/callbacks.rb', line 36

def define_callback(name)
  class_eval "def on_\#{name}(&block)\n  @_sass_callbacks ||= {}\n  (@_sass_callbacks[\#{name.inspect}] ||= []) << block\nend\n\ndef run_\#{name}(*args)\n  return unless @_sass_callbacks\n  return unless @_sass_callbacks[\#{name.inspect}]\n  @_sass_callbacks[\#{name.inspect}].each {|c| c[*args]}\nend\nprivate :run_\#{name}\n"
end