Error 22 Instantiation Error Prolog
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John Gallagher (Denmark). Ulrich Geske (Germany). Neng-Fa Zhou (United States). Christoph Beierle (Germany). Dietmar Seipel (Germany). Mike Elston (New Zealand). Mats Carlson (Sweden). Feliks Kluzniak (United https://www.complang.tuwien.ac.at/ulrich/iso-prolog/error_k States). Samer Abdallah (United Kingdom). Michael Hanus (Germany). Joachim Schimpf (Australia). https://books.google.com/books?id=v6wMBwAAQBAJ&pg=PA71&lpg=PA71&dq=error+22+instantiation+error+prolog&source=bl&ots=QLFdAmBQnA&sig=VCnLqFSKWL6FRuYp4gTdThS9Hwc&hl=en&sa=X&ved=0ahUKEwiv_fCz0cTPAhVQwGMKHerdBSgQ6AEITzAH Daniel Diaz (France). Vítor Santos Costa (Portugal). Klaus DšŖler (Germany). Manuel Hermenegildo (Spain). Jonathan Hodgson (United States). Katsuhiko Nakamura (Japan). Roger Scowen (United Kingdom). David S. Warren (United States). History 2008-02-24: First e-mail report to WG17. 2009-07-17: Action item in Pasadena, 2009. 2009-10-29: Delivered error 22 to WG17 as N213. 2010-07-21: Resolution in Edinburgh: uninstantiation_error. 2010-07-26: N226. 2010-12-13: Superseded by DTC2. 2012-02-14: Published within ISO/IEC 13211-1:1995/Cor.2:2012. Changes under version control. Motivation In ISO/IEC 13211-1:1995 subclause 18.104.22.168 f, a goal open(File, Mode, Stream) has the following error defined: f) Stream is not a variable— type_error(variable, Stream) The argument Stream should be unified with error 22 instantiation a stream-term (7.10.2), more specifically (22.214.171.124): A standard-conforming program shall make no assumptions about the form of the stream-term, except that: a) It is a ground term. b) It is not an atom. c) It uniquely identifies a particular stream during the time that the stream is open. It is implementation dependent whether or not the pro- cessor uses the same stream-term to represent different source/sinks at different times. It is therefore possible for a standard conforming processor to reuse stream-terms for different mutually exclusive file operations. This can be observed in many processors such as SICStus 3, SWI, YAP. YAP version Yap-6.0.0 ?- open(t, write, S), close(S), open(t, write, S). ERROR!! TYPE ERROR- open(t,write,$stream(3)): expected unbound variable, got $stream(3) ?- open(t, write, S), close(S), open(t, write, S2), S == S2. S = S2 = '$stream'(3) ? ; no Whereas the first query produces the required type_error(variable,S), the second clearly shows that success could have been possible. In all other situations, type errors mean semantically failure.
fr√•n GoogleLogga inDolda f√§ltB√∂ckerbooks.google.se - From the viewpoint of an "industrial" this book is most welcome, as one of the most significant demonstrations of the maturity of Prolog. Logic programming is a fascinating area in computer science, which held for years - and still does - the promise of freeing ourselves from programming based on the...https://books.google.se/books/about/Prolog_The_Standard.html?hl=sv&id=v6wMBwAAQBAJ&utm_source=gb-gplus-shareProlog: The StandardMitt bibliotekHj√§lpAvancerad boks√∂kningK√∂p e-bok ‚Äď 674,23¬†krSkaffa ett tryckt exemplar av den h√§r bokenSpringer ShopAmazon.co.ukAdlibrisAkademibokandelnBokus.seHitta boken i ett bibliotekAlla f√∂rs√§ljare»Prolog: The Standard: Reference ManualPierre Deransart, AbdelAli Ed-Dbali, Laurent CervoniSpringer Science & Business Media, 6 dec. 2012 - 272 sidor 0 Recensionerhttps://books.google.se/books/about/Prolog_The_Standard.html?hl=sv&id=v6wMBwAAQBAJFrom the viewpoint of an "industrial" this book is most welcome, as one of the most significant demonstrations of the maturity of Prolog. Logic programming is a fascinating area in computer science, which held for years - and still does - the promise of freeing ourselves from programming based on the "Von Neumann" machine. In addition computer programming has long been for solid theoretical foundations. While conventional engineering, dealing mainly with "analogical complexity", developed over some hundred years a complete body of mathematical tools, no such toolset was available for "digital complexity". The only mathematical discipline which deals with digital complexity is logic and Prolog is certainly the operational tool which comes closest to the logical programming ideal. So, why does Prolog, despite nearly twenty years of development, still appear to many today to be more of a research or academic tool, rather than an industrial programming language? A few reasons may explain this: First, I think Prolog suffers from having been largely assimilated into - and thus followed the fate of - Artificial Intelligence. Much hype in the late 1980 created overexpectations and failed to deliver, and the counterreaction threw both AI and Prolog into relative obscurity. In a way, maybe this is a new chance for the Prolog co