Method: Forwardable#def_instance_delegator

Defined in:
lib/forwardable.rb

#def_instance_delegator(accessor, method, ali = method) ⇒ Object Also known as: def_delegator

Define method as delegator instance method with an optional alias name ali. Method calls to ali will be delegated to accessor.method.

class MyQueue
  extend Forwardable
  attr_reader :queue
  def initialize
    @queue = []
  end

  def_delegator :@queue, :push, :mypush
end

q = MyQueue.new
q.mypush 42
q.queue    #=> [42]
q.push 23  #=> NoMethodError



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# File 'lib/forwardable.rb', line 179

def def_instance_delegator(accessor, method, ali = method)
  line_no = __LINE__; str = %{
    def #{ali}(*args, &block)
      begin
        #{accessor}.__send__(:#{method}, *args, &block)
      rescue Exception
        [email protected]_if{|s| Forwardable::FILE_REGEXP =~ s} unless Forwardable::debug
        ::Kernel::raise
      end
    end
  }
  # If it's not a class or module, it's an instance
  begin
    module_eval(str, __FILE__, line_no)
  rescue
    instance_eval(str, __FILE__, line_no)
  end

end