End of Life Ruby 3.2 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

instance method

Forwardable#def_instance_delegator

def_instance_delegator(accessor, method, ali = method)

# File tmp/rubies/ruby-3.2.0/lib/forwardable.rb, line 188
def def_instance_delegator(accessor, method, ali = method)
  gen = Forwardable._delegator_method(self, accessor, method, ali)

  # If it's not a class or module, it's an instance
  mod = Module === self ? self : singleton_class
  ret = mod.module_eval(&gen)
  mod.__send__(:ruby2_keywords, ali) if RUBY_VERSION >= '2.7'
  ret
end

Define method as delegator instance method with an optional alias name ali. Method calls to ali will be delegated to accessor.method. accessor should be a method name, instance variable name, or constant name. Use the full path to the constant if providing the constant name. Returns the name of the method defined.

Example

class MyQueue
  CONST = 1
  extend Forwardable
  attr_reader :queue
  def initialize
    @queue = []
  end

  def_delegator :@queue, :push, :mypush
  def_delegator 'MyQueue::CONST', :to_i
end

q = MyQueue.new
q.mypush 42
q.queue    #=> [42]
q.push 23  #=> NoMethodError
q.to_i     #=> 1

See also #def_delegators #def_instance_delegators #def_delegator #delegate also in 4.1 · 4.0 · 3.4 · 3.3 · 3.1 · 3.0

‹ prev#def_delegators next ›#def_instance_delegators