Subject: Re: Trivial feature expressions
From: Erik Naggum <>
Date: 24 Aug 2002 05:10:02 +0000
Newsgroups: comp.lang.lisp
Message-ID: <>

* Michael Sullivan
| Is this is the spec, or is there some mathematical basis/use that I'm
| missing?

  I guess the latter.  I have talked about this with a few people (irc) and
  unmathematical people do not even understand that (+) => 0 and (*) => 1.

  The spec is quite clear that `and´, `or´ and a few other obvious identity
  candicates return their identity value.  That is, (operator argument) is
  identical to (operator (operator) argument), which has as a corrollary
  precisely that (operator argument) is identical to argument.  This is very
  sound mathematically.  That there are such hidden gems in Common Lisp
  delight me just as much as grokking some mathematical concept.

Erik Naggum, Oslo, Norway

Act from reason, and failure makes you rethink and study harder.
Act from faith, and failure makes you blame someone and push harder.