From: Robert Klemme <shortcutter@...>
Date: 2011-02-24T17:59:50+09:00
Subject: Re: Q: How to call parent method explistly?

On Wed, Feb 23, 2011 at 1:09 AM, Gary Wright <gwtmp01@mac.com> wrote:
>
> On Feb 22, 2011, at 6:25 PM, makoto kuwata wrote:
>
>> Is it possible to call parent method specifying method name explicitly
>> like super.foobar() or parent::foobar()?
>
> There are a couple of alternatives.
>
> 1) Create an alias of the parent's method and call it instead:
>
> class Child < Parent
>  alias parent_hello hello
>  def _hello(name)
>    parent_hello(name)
>  end
> end
>
> 2) use a method object to reference the parent's method:
>
> class Child < Parent
>  def parent_hello(*args)
>    Parent.instance_method(:hello).bind(self).call(*args)
>  end
>
>  def _hello(name)
>    parent_hello(name)
>  end
> end

Folks, why are you making this so complicated?  Nobody mentions the
standard way of doing this by using "super":

class Parent
  def hello_same_args(a)
     puts a
  end

  def hello_different_args
    puts "We don't need args"
  end
end

class Child < Parent
  def hello_same_args(a)
     super
     puts "now in child"
  end

  def hello_different_args(x)
    super()
    puts "Child got #{x}"
  end
end

irb(main):022:0> Child.new.hello_same_args "ARG"
ARG
now in child
=> nil
irb(main):023:0> Child.new.hello_different_args "ARG"
We don't need args
Child got ARG
=> nil

Only if you want to call a _different_ method in the super class you
need to use one of the other approaches.  But if you think about it,
usually this is not needed.

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/