Re: Intended meaning

From: Sergio Antoy <antoy_at_redstar.cs.pdx.edu>
Date: Fri, 26 Oct 2007 17:00:38 -0700 (PDT)

Michael writes:
> The current operational semantics (e.g., CRWL or also the
> big/small step semantics in
> http://www-ps.informatik.uni-kiel.de/~mh/papers/JSC05.html does
> not specify any sharing over nondeterministic branches of a
> computation. Thus, both are the same.

It makes sense. However, the Curry Report may lead to believe
differently. Section 3 allows a reduction in either argument of a
disjunctive expression. Section 2.3.1 says that several
occurrences of the same variable are always shared (in italic).
Given:

    test = 1+x ? zero x where x free

the following computation complies with these requirements:
    
    test
      -> 1+x ? zero x where x free
      -> {x->0} 1+0 | {x->0} 0
      -> {x->0} 1 | {x->0} 0
    
but it is not intended.

Sergio
_______________________________________________
curry mailing list
curry_at_lists.RWTH-Aachen.DE
http://MailMan.RWTH-Aachen.DE/mailman/listinfo/curry
Received on Sun Oct 28 2007 - 19:01:37 CET

This archive was generated by hypermail 2.3.0 : Mon Nov 11 2019 - 07:15:07 CET