[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
- To: JONL at MIT-MC
- From: Alan Bawden <ALAN at MIT-MC>
- Date: Thu, 18 Sep 80 19:28:00 GMT
- Cc: BUG-LISP at MIT-MC
- Original-date: 18 September 1980 15:28-EDT
Date: 18 SEP 1980 0951-EDT
From: JONL at MIT-MC (Jon L White)
Date: 18 September 1980 02:35-EDT
From: Alan Bawden <ALAN at MIT-MC>
I was looking at how SUBLIS worked...
. . .
Suppose I went nuts trying to figure out why the SUBLIS returned the wrong
answer, and why my property lists were being REMPROPed behind my back.
I suppose this comment has an element of truth in it (e.g., "went nuts ...");
but the "clever" version of SUBLIS dates back to LISP 1.5 days, and at one
time was a "feature" that you could put your own SUBLIS properties.
When the Moonual was written these features didn't get documented, so I
suppose it would be good to use some other property name now.
The "feature" isn't much of a feature since:
1) SUBLIS isn't careful to not remove SUBLIS properties that it didn't put there.
2) It only works to put a SUBLIS property on the front of the property list.
3) It doesn't work to say (sublis nil ...). (It doesn't look at ANY properties
in that case.)
If you are going to go to the trouble to use some other property, why
not go all the way and rewrite it to not use property lists at all!
(More efficient in the common, small-alist case.)