Subject: Re: Name for the set of characters legal in identifiers From: Erik Naggum <firstname.lastname@example.org> Date: 14 Jan 2004 21:36:55 +0000 Newsgroups: comp.lang.lisp Message-ID: <3283105015922595KL2065E@naggum.no> * james anderson | the hypothesis was that the constituent traits as set out in the | table on standard and semi-standard characters, which traits are not | supposed to be clobbered by set-syntax-from-char, would be useful to | characterise the set of characters which could be used in symbol | names without explicit escaping. That does not appear to be an unreasonable hypothesis, but it was not the hypothesis you tested. You tested whether a string of three characters, varying the middle one, would be read as a symbol or would signal an error. Any number of middle characters that cause a termination of the reader algorithm will produce a symbol read from the first character, a letter. | i would have expected the same status as that for #\: to apply to | whitespace characters and to rubout. But (read-from-string "a b") will return a symbol, namely A, when the constituent trait of the space is /invalid/. You did not test the length or any other property of the symbol-name of the returned symbol, only that it did not error. The secondary value returned from READ-FROM-STRING should be educational. -- 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.