RubyでSwiftのOptionalChainingモドキ

optional_ruby.rb

class NilClass
  def method_missing(args)
    nil
  end
end

module Optional
  def method_missing(method_name, *args)
    if method_name =~ /\?$/
      search_name = method_name[0...-1]
      if respond_to?(search_name)
        __send__(search_name, *args)
      else
        nil
      end
    else
      super
    end
  end
end

class Bar
  def bar
    puts "bar"
  end
end

class Foo
  include Optional

  def foo
    puts "foo"
    Bar.new
  end
end

Foo.new.foo?.bar
p Foo.new.bar?.foo