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Reply-To: "Kumar Balachandran" <kumarbalac...@earthlink.net>
From: "Kumar Balachandran" <kumarbalac...@earthlink.net>
Newsgroups: comp.lang.lisp
References: <jkCma.9$NE4.382@paloalto-snr1.gtei.net> <20030414135114.24021.00000821@mb-ch.aol.com> <b7gl6c$sn9$07$1@news.t-online.com> <20030415104420.G13181@lain.cheme.cmu.edu> <b7hrhm$o6b$07$1@news.t-online.com> <20030415182228.H13181@lain.cheme.cmu.edu> <160420030037089214%nospam@iam.invalid> <878yua4p14.fsf@bird.agharta.de> <160420031526227070%nospam@iam.invalid>
Subject: Re: Implementation Favoritism, a question of Lisp mindsets
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Date: Fri, 18 Apr 2003 06:06:04 GMT
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I can understand the standard simple examples that are typically quoted, and
I can easily think in terms of machine language to figure out how call/cc
would work. However, any serious scheme code with call/cc seems so bloody
obfuscated to me, I always give up trying to understand it.

If programs are a method of  communicating with other programmers, then
call/cc has failed miserably, rather like my poem below.
    Little Jack Horner
        sat in a corner
    Coding and Scheming against LISP.

    He called Forth
        obfuscation galore
    but on continuation felt something amiss.

Seriously, I have never found the patience to really grok this wonderful
thing. I can always achive the set goals in a very readable manner in other
ways.

K.

>
> A note to other Lisp newbies like me:
>
> There is no reason to fear continuations.  They are merely a way to
> jump out of a function before the function would normally finish.
>
> The function is just "paused" at the point where the continuation was
> activated in the middle of the function.
>
> The function can then be "resumed" later if desired, at the exact point
> in the code where it was paused or interrupted.
>
> As you can imagine, jumping out of a function before it is normally due
> to finish can cause all sorts of problems.
>
> Jumping back into the middle of a 'suspended' function can also cause
> all sorts of problems.
>
> Despite all this, continuations allow for all sorts of flexibility if
> they are used when no other means is available to solve a particular
> programming problem.
>
> Mark-