PLOGHELP PROLOG_VALOF                       Kathryn Seifert  August 1986
                                   Revised by Simon Nichols, August 1987

A POP-11 procedure which returns the current value of a Prolog predicate

    prolog_valof(<word:W>, <integer:I>) -> <procedure:P>
    <procedure:P> -> prolog_valof(<word:W>, <integer:I>)

Keywords: Prolog, mixed language programming, continuations,
          prolog terms


-prolog_valof- returns a continuation passing procedure P (see
PLOGHELP * POPTOPLOG, PLOGHELP * MIXED_LANGUAGES and DOC * CONTINUATION)
as specified by the word W and the integer I, which represent the functor
name and arity of a Prolog predicate.

A mishap will occur if the specified predicate currently has no
definition.

The updater of prolog_valof assigns the continuation passing procedure P
to be the value of the Prolog predicate with functor name W and arity I.
Subsequently, this predicate can be invoked normally from Prolog.


-- RELATED DOCUMENTATION ----------------------------------------------

DOC * CONTINUATION
 Explanation of continuation passing procedures in POP-11

PLOGHELP * MIXED_LANGUAGES
 Overview of interface between Prolog and other languages

PLOGHELP * POPTOPLOG
 How to call Prolog from POP-11

PLOGHELP * PROLOG_INVOKE
 POP-11 procedure which invokes a Prolog term

PLOGHELP * TERMSINPOP
 Facilities for manipulating Prolog terms and variables in POP-11

TEACH * CONTINUATIONS
 Introduction to DOC * CONTINUATION

--- C.all/plog/help/prolog_valof ---------------------------------------
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