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# frozen_string_literal: true
module Facade
# The version of the facade library
FACADE_VERSION = '1.2.2'
# The facade method will forward a singleton method as an instance
# method of the extending class. If no arguments are provided, then all
# singleton methods of the class or module become instance methods.
#
# Existing instance methods are NOT overridden, but are instead ignored.
#
# Example:
#
# require 'facade'
#
# class MyString < String
# extend Facade
# facade File, :dirname, :basename
# end
#
# s = MyString.new('/home/djberge')
# s.basename # => 'djberge'
# s.dirname # => '/home'
#
def facade(klass, *methods)
methods = methods.flatten
if methods.empty? # Default to all methods
methods = klass.is_a?(Class) ? klass.methods(false) : klass.public_instance_methods(false)
end
methods -= instance_methods.map(&:to_sym) # No clobber
# Cache the extended object for modules to avoid creating it on every call
mod_proxy = klass.is_a?(Module) && !klass.is_a?(Class) ? Object.new.extend(klass) : nil
methods.each do |method_name|
define_method(method_name) do
meth = klass.is_a?(Class) ? klass.method(method_name) : mod_proxy.method(method_name)
if meth.arity.zero?
meth.call
else
meth.call(self)
end
end
end
end
end
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