Path: utzoo!attcan!uunet!mcsun!ukc!edcastle!aiai!jeff
From: jeff@aiai.ed.ac.uk (Jeff Dalton)
Newsgroups: comp.lang.scheme
Subject: Re: extension languages can be darn small, yet still powerfull
Message-ID: <3442@skye.ed.ac.uk>
Date: 24 Sep 90 17:44:41 GMT
References: <5879.9008301913@subnode.aiai.ed.ac.uk> <6073@castle.ed.ac.uk>
Reply-To: jeff@aiai.UUCP (Jeff Dalton)
Organization: AIAI, University of Edinburgh, Scotland
Lines: 66

In article <6073@castle.ed.ac.uk> expc66@castle.ed.ac.uk (Ulf Dahlen) writes:
>In article <5879.9008301913@subnode.aiai.ed.ac.uk> jeff@aiai.edinburgh.ac.UK (Jeff Dalton) writes:

>>> Many of the lisp-haters that I am thinking of used the Xerox InterLisp
>>> workstation environment.  What got many people were the structured
>>> editors.

>>I couldn't stand DEDIT (or whatever it was called).  Indeed, I'm not
>>a big fan of structure editors in general.  Lisp is my favorite language
>>nonetheless.

>Why not? I found it much better than any Emacs-style editor when programming
>in Lisp. Of course, SEDIT (the successor to DEDIT) is completely different
>and *very* much easier to use. Try it.

I suppose we ought to move this to a different newsgroup if it goes
on much longer (perhaps Alt.religion.computers is the right place),
but I suppose I can risk a brief reply.

There's a big difference between SEDIT and DEDIT.  I don't much mind
SEDIT, but then it's a lot closer to the Emacs-like editors than DEDIT
is.  However, many (at least) of the people who prefer structure
editors felt the same way when the editor was DEDIT.  This suggests
that there is a fairly fundamental disagreement in there somewhere.

I found DEDIT cumbersome to use.  Moreover, I want to use the same
editor for both text and programs (especially since programs contain
text).  I also find that structure editors don't indent programs very
well.  All I have to do in GNU Emacs (when using a good Lisp mode) is
make the line breaks (and, very rarely, make a small adjustment).
This isn't much more work, but I find a very noticeable improvement in
the results.  Finally, I like text files.  I can mail them to other
people, they can load them into their Lisp, and they still look just
like I intended.  Code produced with a structure editor often looks
good only when you use the same structure editor to read it.

>Since Lisp is a structured language and since much of the teaching tries
>to get this point across, I find structure editors very appropriate to use.
>Most students either don't understand Lisp or they understand it _and_
>like structure editors. That's my experience anyway.

But it's not my experience.  I know quite a few people who understand
Lisp, like Lisp, and dislike structure editors.

Perhaps the students you know are like the ones in the Edinburgh AI
Department.  (I note that you're in Edinburgh now, but that's a fairly
recent move, I think, so I don't really know about the students you've
encountered.)

Some of the Ed AI students who use Lisp use Xerox D-machines; most
of the others use micro-emacs.  Well, micro-emacs is a *terrible*
editor for Lisp, because it doesn't have a proper Lisp mode.  So
I'm not surprised when *those* students either don't understand 
Lisp or prefer structure editors.

Moreover, people who teach Lisp often assume structure editors are
better, even if they haven't used a structure editor or a text editor
that has a good Lisp mode.  Students pick up this attitude, but not
because any of the people involved have relevant experience.

Of course, some people have given both kinds of editors a fair
chance and happen to prefer structure editors.  I don't have any
quarrel with that so long as they are willing to accept the opposite
decision in the same way.

-- Jeff