Overview

Various aspects of the program state can be inspected: The clauses of all or selected dynamic procedures, currently available atoms, user defined predicates, source files of predicates and clauses, predicate properties and the current load context can all be accessed by calling the predicates listed in ref-lps-ove. Furthermore, the values of prolog flags can be inspected and, where it makes sense, changed. The following predicates accomplish these tasks:

listing

list all dynamic procedures in the type-in module

listing(P)

list the dynamic procedure(s) specified by P

current_atom(A)

A is a currently available atom (nondeterminate)

current_predicate(A,P)

A is the name of a predicate with most general goal P (nondeterminate)

predicate_property(P,Prop)

Prop is a property of the loaded predicate P (nondeterminate)

prolog_flag(F,V)

V is the current value of Prolog flag F (nondeterminate)

prolog_flag(F,O,N)

O is the old value of Prolog flag F; N is the new value

prolog_load_context(K,V)

find out the context of the current load

source_file(F)

F is a source file that has been loaded into the database

source_file(P,F)

P is a predicate defined in the loaded file F

source_file(P,F,N)

Clause number N of predicate P came from file F