From: Trans <transfire@...>
Date: 2005-11-06T15:07:10+09:00
Subject: block returns and hash element returns

A question and a thought (or two).

Is there a way to return from a block without returning from the whole
method? Eg.

  # This behavior
  def double_collect( array )
    array.collect { |v| v*2 }
  end

  # Nope, returns from double_collect
  def double_collect( array )
    array.collect { |v| return v*2 }
  end

  # Nope, returns only first iteration
  def double_collect( array )
    array.collect { |v| break v*2 }
  end

Would something like #local_return be useful?

The reason I ask is b/c I was also thinking about a possbile special
form of 'return' that can handle hash assocations:

  def double_collect( array )
    array.collect { |v| local_return v => v*2 }
  end
  double_collect( [1,2,3] )  #=> { 1=>2, 2=>4, 3=>6 }

Presently I use a facet called #graph to do this:

     array.graph { |v| [v, v*2] }

But returning that array just feels wrong (not to mention inefficient).

Thanks,
T.