From: Paul Prescod <paul@...>
Date: 2003-03-24T12:02:08+09:00
Subject: Re: Ruby lecture slides (was Strong advantages over Python)

Greg McIntyre wrote:
> Jim Weirich <jweirich@one.net> wrote:
> 
>>Yes and no.  Although they are entirely different things, they both
>>are used for do "iteration-like" stuff in their respective languages. 
>>That and the fact they both use the keyword "yield" (although with
>>complete different semantics!) leads people to confuse the two.
> 
> Okay, so what if, instead of saying "This functionality has been added
> to Python recently as generators," I said that "This functionality has
> been added to Python recently using generators"? I mean. If generators
> are a more powerful and general construct, they should be able to do
> what Ruby blocks can, plus more.

Generators are not a more general construct. They are specific to the 
problem of constructing an iterator without doing a bunch of state 
book-keeping. You can't build generators out of blocks and you can't 
build blocks out of generators. You can build generators out of 
continuations, though.

  Paul Prescod