Subject: Re: quick question From: Erik Naggum <firstname.lastname@example.org> Date: 15 Nov 2000 01:06:58 +0000 Newsgroups: comp.lang.lisp Message-ID: <email@example.com> * Jonathan Wohlgelernter | a quick question from inexperienced LISP user: | what does the # symbol do, as in the following code: | | (DO ((RULE-# 1 (+ 1 RULE-#)) | (MAX-NUMB (KEYWD-NUMB-DECOMPS KEY))) | | (( > RULE-# MAX-NUMB) NIL) ; End Test # is a constituent character in that context. As such, it does nothing (special) or exactly the same as the character -. (Note that in the context of Lisp, "symbol" should not be confused with character even though the two are sometimes interchangeable in other contexts.) * Barry Margolin <firstname.lastname@example.org> | In Common Lisp '#' is used as a prefix character for a number of special | sequences, but that's obviously not going on here. It looks like it's | written in a dialect of Lisp where # is treated as an alphanumeric | character, since it's just using it as part of the variable name, as an | abbreviation for "number". Well, # is a non-terminating macro character in Common Lisp, so symbol names like RULE-# are perfectly valid, although somewhat unusual, such as because people think it is a terminating macro character... #:Erik -- ALGORITHM: a procedure for solving a mathematical problem in a finite number of steps that frequently involves repetition of an operation. ALGOREISM: a procedure for solving an electoral problem in a finite number of steps that frequently involves repetition of an operation.