From: David Alan Black <dblack@...>
Date: 2001-11-29T22:10:00+09:00
Subject: [ruby-talk:26888] Re: overload possible?

Hello --

On Thu, 29 Nov 2001, Rich Kilmer wrote:

> excellent idea...how about this refactoring...
>
> module Overload
>   def overload(args, *types)
>     return if args.length != types.length
>     args.each_index {|i| return if args[i].type.to_s != types[i].to_s}

You could pass around classes instead of symbols (unless there a
drawback to that I'm not seeing), in which case the above could be:

     args.each_index {|i| return if args[i].type != types[i]}

and then:

> if __FILE__ == $0
>   class Fred
>     include Overload
>     def hello(*args)
>       overload(args, :Fixnum, :String, :Float) do

       overload(args, Fixnum, String, Float) do ....

etc.

Also:

>    raise TypeError,
>    "Invalid Signature: #{args.collect {|a| a.type.to_s}.join(', ')}"

will work OK without the to_s.

Hmmmm....  I'm beginning to see what Robert F. means about a form of
#map where you send it a method name:

  def overload(args,*types)
    return unless args.map(:type) == types
    ...

would certainly be concise.


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav