Path: utzoo!mnetor!uunet!husc6!cmcl2!nrl-cmf!ames!pasteur!ucbvax!golfer.Dayton.NCR.COM!pierce From: pierce@golfer.Dayton.NCR.COM Newsgroups: comp.lang.scheme Subject: How can you do things like ?X -> (*var* x) without Read Macros ? Message-ID: <8803231941.AA16664@SCUBED.ARPA> Date: 23 Mar 88 18:29:00 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 17 Sometimes it is very useful to hide some underlying implementation details when writing systems such as inference engines. Since Scheme doesn't have ability to handle read macros then is it possible to do something like the following in a differnet way ? where "x" is a variable and "?" is a read macro and the "?" read macro reads the next character, which is "x" and transforms "?X" into the following list structure (*var* x) . This representation is useful to the underlying code and the "?x" is useful to a user to designate unifiable variables in a backward or forward chaining rule. Any and all responses are appreciated. thanks in advance, Gene Pierce --