XPost: comp.theory, sci.math, comp.lang.prolog   
   From: polcott333@gmail.com   
      
   On 12/10/2025 12:10 PM, Tristan Wibberley wrote:   
   > On 10/12/2025 14:10, olcott wrote:   
   >   
   >> BEGIN:(Clocksin & Mellish 2003:254)   
   >> Finally, a note about how Prolog matching sometimes differs   
   >> from the unification used in Resolution. Most Prolog systems   
   > ...   
   >   
   >> 1 The Prolog standard states that the result is undefined if   
   >> a Prolog system attempts to match a term against an uninstantiated   
   >> subterm of itself, which means that programs which cause this to   
   >> happen will not be portable. A portable program should ensure that   
   >> wherever an occurs check might be applicable the built-in predicate   
   >> unify_with_occurs_check/2 is used explicitly instead of the normal   
   >> unification operation of the Prolog implementation. As its name   
   >> suggests, this predicate acts like =/2 except that it fails if an   
   >> occurs check detects an illegal attempt to instantiate a variable.   
   >> END:(Clocksin & Mellish 2003:254)   
   >>   
   >> Clocksin, W.F. and Mellish, C.S. 2003. Programming in Prolog   
   >> Using the ISO Standard Fifth Edition, 254. Berlin Heidelberg:   
   >> Springer-Verlag.   
   >   
   >   
   > You're a veritable treasure-trove.   
   >   
      
   You seem to have proved to know this material quite well.   
   Of people that visit this forum you seem to be in the top 10%.   
      
   --   
   Copyright 2025 Olcott

   
      
   My 28 year goal has been to make 
   
   "true on the basis of meaning expressed in language"
   
   reliably computable.

   
      
   This required establishing a new foundation
   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)