From: Louis J Scoras <louis.j.scoras@...>
Date: 2006-11-17T00:46:08+09:00
Subject: Re: #returning and #tap

I think where returning really makes a difference is with local
variables.  If you have some code where you want to initialize a local
variable in a block and then use it afterward your up the creek.

    def foo(a)
      a.each do |x|
        (b ||= []) << x
      end
      b # => oops
    end

    a = [1,2,3]
    p foo(a)

What you need to do, of course, is just initialize before the block:

    def foo(a)
      b = []
      a.each do |x|
        b << x
      end
      b
    end

Ugly.  Sorry, it just is.  It is much more readable to use returning.

    def foo(a)
      returning [] do |b|
        a.each do |x|
          b << x
        end
      end
    end

On another note, I don't buy the argument that this is a bad practice
because the you no longer look for the last value to see what is
returned.  That's exactly what you do.  The last element in this
function is the 'end' of the returning block.  What does returning
return?  I think its pretty obvious personally.



-- 
Lou.