From: Alex McHale <alexmchale@...>
Date: 2004-06-02T05:41:15+09:00
Subject: Re: Blocks and Closures

Oooh I understand now.  In fact I had given my own answer initially,
by noting that bl is the proc object.

Thank you for the clarification.  I come to love Ruby more and more
every day ...

For me, Ruby is a lot like vim.  I've been using it for years, and I
still learn something new about it every day.

On Wed, 2 Jun 2004 05:38:19 +0900, Joel VanderWerf
<vjoel@path.berkeley.edu> wrote:
> 
> Alex McHale wrote:
> > Alright, while that is very confusing to me (not the concept, I
> > understand what you said, just why the precedence is different), you
> > raise another question.
> >
> > In your example, you use the &bl syntax.  I understand that if you
> > want the proc object, that is the syntax to use, but why use it in
> > that case?
> >
> > Wouldn't this give identical results?
> >
> > def foo(*args)
> >     puts "foo got the block" if yield
> > end
> >
> > etc?  Is the reason to use this construct because you want to demand
> > that a block be passed?
> >
> > And on that note, is there a syntax to determine whether or a block
> > was passed to the method, in the syntax of my construct?
> 
> You're right, there's no reason to use the &bl notation. You can use the
> Kernel#block_given? method:
> 
> def foo(*args)
>     puts "foo got the block" if block_given?
> end
> 
> But using 'if yield' is different: it tests the return value of the
> block, not the existence of the block.
> 
>