[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Destructive operations
- To: navajo!Timothy.Freeman%theory.cs.cmu.edu@navajo.stanford.edu
- Subject: Destructive operations
- From: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
- Date: Wed, 7 Jan 87 11:38:23 pst
- Cc: navajo!common-lisp%sail.stanford.edu@navajo.stanford.edu, navajo!gross%sam.cs.cmu.edu@navajo.stanford.edu
- In-reply-to: navajo!Timothy.Freeman@theory.cs.cmu.edu's message of Wednesday, 7 January 1987 11:37:53 EST
Right you are. I was assuming too much. Just because something may
have horrible consequences doesn't necessarily make it illegal.
Modifying constants in compiled code has the same legal status as
modifying the SYMBOL-NAME string of a symbol. ``It is an extremely
bad idea to modify'' a constant in compiled code. ``Such a
modification may tremendously confuse'' any function which contains a
constant EQUAL to the one being modified. For similar reasons, it is
a bad idea to modify any object which is used as a key in an EQUAL
hash table (this problem is unfortunately not mentioned in CLtL).