From: dblack@...
Date: 2003-01-10T03:39:00+09:00
Subject: Re: so it seems there is no way to pass argument lists?

Hi --

On Fri, 10 Jan 2003, Tom Sawyer wrote:

> so it seems there is no way to pass argument lists?
>
> 	def throwem
> 		return *[1, 2, 3]
> 	end
>
> 	def catchem(*args)
> 		return args.length
> 	end
>
> 	puts catchem throwem  #--> 1
>
> the astrisk(*) amounts to nothing. :-(

There's nothing you can't do, by way of passing arrays around; you
just have to process them according to what you've asked Ruby to do.
In this case, if you have:

   def catchem(*args)

then you have to get at args[0] to see the first argument -- which, in
this case, is itself an array.  (It's not that the * in throwem does
nothing; it's that the way Ruby passes multiple return values is by
packaging them into an array.)

  def throwem
    return 1,2,3
  end

  def catchem(*args)
    args[0].length
  end

  puts catchem(throwem)    # 3


David

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