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From: mark rostron <markro2@atlantis.rosemount.com>
Subject: a question regarding assertions from a neophyte
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Date: Tue, 13 Feb 1996 16:30:43 GMT
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Hi,
prolog behaves as follows regarding accessing hitherto unreferenced predicates:

if I say:

junk.

prolog will respond the first time with 'undefined predicate junk/0'.

if I say:

assertz(junk).
retract(junk).
junk.

then prolog responds with 'no'.

is this standard or implementation dependant? It occurs in both SWI and binProlog.
IF it is standard, is the solution as simple as putting forward declarations of all 
your predicates into the program?

mr

