From: Kaldrenon <kaldrenon@...>
Date: 2007-08-22T21:59:57+09:00
Subject: Re: how to dump contents of an array as parameters

On Aug 22, 7:11 am, Akif Tokuz <akifuse...@gmail.com> wrote:
> Stefano Crocco wrote:
> > You need to do this:
>
> > Track.new(*[15, 'b'])
>
> > I hope this helps
>
> > Stefano
>
> Thank you Stefano. It worked.
>
> Akif,
> --
> Posted viahttp://www.ruby-forum.com/.

Just to expand (pun?) the concept:

the * operator, when applied to method arguments, work two ways, if I
understand correctly:

In a method call, putting * before an array breaks it apart into its
elements and passes them as individual arguments to a method. So
  x.do_stuff(a,b,c,)
is equivalent to
  x.do_stuff(*[a,b,c])
or
  y = [a,b,c]
  x.do_stuff(*y)

In a method declaration, * can be used to collect an undetermined
number of arguments into an array. Suppose that you have a method that
accepts optional arguments, and depending on the options there could
be 1, 2, or 3 values passed in. One way (there are others) to handle
that would be to make the method look like this:

def do_stuff(*args)
  if args.length > 2
    puts "optional stuff"
  else
    puts "default stuff"
  end
end


I believe I've gotten this right, but I'm something of a Nuby myself.
Any comments or corrections of my explanation would be greatly
appreciated.

HTH,
Andrew