From: Hugh Sasse Staff Elec Eng <hgs@...>
Date: 2004-03-04T20:07:55+09:00
Subject: Re: concerns about Proc,lambda,block

On Thu, 4 Mar 2004, Yukihiro Matsumoto wrote:

> Hi,
>
> In message "Re: concerns about Proc,lambda,block"
>     on 04/03/03, Mauricio Fern�ndez <batsman.geo@yahoo.com> writes:
>
> |do you want to keep Proc and lambda as separate things (like Class &
> |Module) or would you consider merging them and reaching a compromise on
> |their semantics?
>
> My current stand point is that conceptually lambda returns a Proc
> wrapped by argument checker and local jump handler, thus a Proc from
> lambda is still a Proc.  If you really wish to distinguish those two
> (wrapped proc and unwrapped proc), you still have chance to persuade
> me.

I'm not sure what the right thing to do would be: sometimes
simplicity is acheived by similarity, other times by difference.
However, I think some kind of reflection would be useful, whatever
you decide.  Maybe a wrapped?() method might be useful, so at least
when debugging we can ask the code "Are you a wrapped proc or not?"

Just thinking out loud: maybe wrapped() and unwrapped() could return
a wrapped and an unwrapped version of the sender proc respectively,
allowing coversion between the two?  If the proc already is
(un)wrapped, then (un)wrapped() is just dup(), perhaps?

I think this would still leave blocks as "non-objects" because they
cannot occur except after a method, so there'd be no danger of
trying to wrap or unwrap a block.

>
> 							matz.
>
        Hugh