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From: Pereira%SRI-AI@sri-unix.UUCP
Newsgroups: net.lang.prolog
Subject: 'setof' Again ...
Message-ID: <13253@sri-arpa.UUCP>
Date: Tue, 1-Nov-83 11:39:12 EST
Article-I.D.: sri-arpa.13253
Posted: Tue Nov  1 11:39:12 1983
Date-Received: Sun, 6-Nov-83 18:58:48 EST
Lines: 18

Some contributors to this Digest have suggested that using 'setof'
rather than 'findall' is just a matter of taste, thus justifying
their use of the name 'setof' for 'findall'. In previous notes,
I gave clear examples that show this is NOT a matter of taste:

- 'setof' has a proper semantics in terms of finite failure,
   'findall' does not;

- interchanging goals in a program with 'findall' may produce
  different solutions, but not with 'setof'.

Warren's 'setof' is RIGHT in a way that 'findall' isn't. Please
stop muddling a simple matter !

-- Fernando Pereira

PS: Now don't come back and start arguing about what 'right' means.
We've been subjected to more than enough Humpty Dumpty semantics.