Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!ub!uhura.cc.rochester.edu!rochester!kodak!ispd-newsserver!ism.isc.com!chine!marv From: marv@chine.ism.isc.com (Marvin Rubinstein) Newsgroups: comp.lang.misc Subject: Re: Halting Problem Solved! Film at 11! (Was Re: definitions) Message-ID: <1991May17.005905.5421@ism.isc.com> Date: 17 May 91 00:59:05 GMT References: <1991May14.054813.18427@sbcs.sunysb.edu> Sender: usenet@ism.isc.com (Ism Usenet News) Organization: Interactive Systems Corp. Lines: 32 Followup-To: comp.lang.misc Distribution: Organization: Interactive Systems Corp., Santa Monica, CA Keywords: In article mathew@mantis.co.uk (CNEWS MUST DIE!) writes: >jallen@csserv2.ic.sunysb.edu (Joseph Allen) writes: >[ On solving the halting problem: ] >> >> No, it can be done! Really! Just don't allow loops, gotos or recursion. > >Or I/O. > >> Now who wants to write a compiler in a language with these restrictions? > >More importantly, who wants to use it? Historical note: The first digital machine that I used (in 1953) had these properties. It was an IBM CPC (Card Programmed Calculator). The machine did not have a program store (it did have a small data store). The way it worked was that it read a card which contained a few instructions. The instructions were executed and the next card was read. The process continued until it ran out of cards and halted. I used it to reduce wind tunnel data. One of the models I tested was a Sparrow missile. I noticed that Sparrows were used in our latest war. The machine was extremely useful compared to the alternative, pencil, paper and a desk calculator. BTW: Most early machines were called calculators. Computer was a job title. Marv Rubinstein