call
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6.2.14. call
calls its Argument
SYNOPSIS
EXPORT goal(void). call(goal(arguments))
SYNTAX
call(Goal) (i)
ARGUMENTS
void(Goal) (i) the goal or compound goal to be called
DESCRIPTION
Standard PROLOG call predicate.
Call() is able to call all 'exported' predicates. Goal may consist of compound goals. The number of
arguments of the called predicates is restricted to 10. This restriction only applies to the 'top
level' of the predicate. Any Argument itself may be a struct and contain an unlimited amount
components.
In most PROLOG implementations a call just fails if the predicate called does
not exists. However, in BAP we issue a warning because in most cases you call
a not available predicate it is due to a program error. You may check the existence
of a predicate by the use of the exists
() predicate, thus avoiding this warning.
If you call predicates that are defined in different modules, you may have to ensure that these
modules are loaded already.
EXAMPLE
read(X),read(Y), call(( X ; Y )). read(X), exists(X), call(X).
ERRORS
Warning and failure if the Goal predicate is not currently available in the symbol table.
LAYERS
prolog-process, client-server, object
RELATED PREDICATES
exec , exists , xcall , load , load_all
BAP Online Manuals : Library Reference : Library by Name : call
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