Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!bonnie.concordia.ca!clyde.concordia.ca!nstn.ns.ca!news.cs.indiana.edu!samsung!crackers!jjmhome!smds!sw From: sw@smds.UUCP (Stephen E. Witham) Newsgroups: comp.lang.misc Subject: Re: On whether C has first-class composable functions Summary: Languages (& Turing) describe abstract machines Message-ID: <323@smds.UUCP> Date: 14 Feb 91 16:25:57 GMT References: <1991Feb7.150537.9257@spool.cs.wisc.edu> Organization: SMDS Inc., Concord, MA Lines: 21 In article <319@smds.UUCP> rh@smds.UUCP (Richard Harter) writes: ...about real machines not being Turing equivalent, in response to Dan Bernstein's saying something about "real languages." Richard, Richard. Dan, Dan. A language is a description of an abstract machine. Description Limited implementation Abstract machine ------------------ ------------------------ ------------------------ C standard Real Von Neuman machine Infinite "C machine" Turing's real "Turing machine" with Abstract Turing machine description of his finite tape imaginary machine (Hmm. But does C require that pointers have a finite number of bits? How about longs? If so, how can you address infinite memory? What about Pascal?) --Steve Witham Back-to-work-for: SMDS, Inc., Concord, MA