From: Daniel Brockman <daniel@...>
Date: 2005-08-07T05:34:14+09:00
Subject: Re: new block notation

"Trans" <transfire@gmail.com> writes:

> I'm confused myself b/c I don't see any difference between
> a block and a lambda. I was trying to understand what it
> is, and for a moment I thought somone one saying that
> 'self' was different in the two cases, but its not.
> Let me back up. What is the difference?

Lambdas (or procs) are anonymous functions.  Blocks are what
you pass to methods using `foo {...}' or `foo(&...)'.

Blocks are more primitive than lambdas; you can create a
lambda by passing a block to the Kernel#lambda method.

You can convert a lambda to a block by using the `&' syntax
(as in `&lambda {...}'), and the other way around by calling
Proc.new or using the `def foo(&block)' syntax.

So, to rehash:  Blocks are what go in between `{' and `}',
while procs, or lambdas, or (anonymous) functions, are
objectified blocks (instances of the Proc class).

-- 
Daniel Brockman <daniel@brockman.se>