From: "Ara.T.Howard" <ahoward@...>
Date: 2003-11-19T12:42:20+09:00
Subject: Re: "stereotyping" (was: Re: Strong Typing (Re: Managing metadata    about attribute types)LONGEST SUB?

On Wed, 19 Nov 2003, T. Onoma wrote:

> I wonder if it would be helpful to be able to ask a method what the
> respond_to? requirements of its parameters will be.
> 
>    def read(io_object) io_object.read end
> 
>    method(:read).duck_signiture  # => [ [:read] ]
> 
> then you might
> 
>    def read(io_object) self.method(:read).duck_signiture[0].each { |m| fail
>    "Not Responsable Object" unless io_object.respond_to?(m) } io_object.read
>    end
> 
> a shorthand would be nice.

how about simply

  obj.respond_to? :read # => true

  obj.respond_to? :read, IO # => true

  obj.respond_to? :read, IO, Proc # => false


in otherwords

  class Object
    def respond_to? meth
      # old stuff...
    end
  end

becomes

  class Object
    def respond_to?(meth, *signature)
      # new stuff...
    end
  end

nice and backward compatible.  easy to remember.

-a
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