4.2.6 Exceptions Related to Procedure Calls

All predicates that take a call argument will raise the following exceptions:

instantiation_error
Module prefix or goal uninstantiated.
type_error
Goal not a callable.
existence_error
Procedure does not exist.
context_error
Declaration or clause construct called as procedure.

The reference page for such predicates will simply refer to these as “Call errors” and will go on to detail other exceptions that may be raised for a particular predicate.


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