From: Joel VanderWerf <vjoel@...>
Date: 2006-12-21T09:54:21+09:00
Subject: Re: Discovering the number of return arguments requested.

Brad Phelan wrote:
> Is it possible ( and I think not ) that you can discover if any return 
> arguments are requested when a method is called.
> 
> Eg:
> 
> def foo
>   if nargout == 1
>      "bar"
>   end
> end
> 
> a = foo # nargout == 1
> foo     # nargout == 0
> 
> 
> This would be useful in certain patterns where you only want to
> create a return value and consequently a new object if it is
> actually required.

One option is yield:

def foo
   yield "bar" if block_given?
end

a = nil

foo {|x| a=x}
#or:
#foo {|a|} # this doesn't work in 1.9 IIRC

-- 
        vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407