5.14 Module properties

The following predicates can be used to query the module system for reflexive programming:

[nondet]current_module(?Module)

True if Module is a currently defined module. This predicate enumerates all modules, whether loaded from a file or created dynamically. Note that modules cannot be destroyed in the current version of SWI-Prolog.

module_property(?Module, ?Property)

True if Property is a property of Module. Defined properties are:

class(-Class)

True when Class is the class of the module. Defined classes are

user

Default for user-defined modules.

system

Module system and modules from <home>/boot.

library

Other modules from the system directories.

test

Modules that create tests.

development

Modules that only support the development environment.

file(?File)

True if Module was loaded from File.

line_count(-Line)

True if Module was loaded from the N-th line of file.

exports(-ListOfPredicateIndicators)

True if Module exports the given predicates. Predicate indicators are in canonical form (i.e., always using name/arity and never the DCG form name//arity). Future versions may also use the DCG form and include public operators. See also predicate_property/2.

exported_operators(-ListOfOperators)

True if Module exports the given operators. Each exported operator is represented as a term op(Pri,Assoc,Name).

set_module(:Property)

Modify properties of the module. Currently, the following properties may be modified:

base(+Base)

Set the default import module of the current module to Module. Typically, Module is one of user or system. See section 5.9.

class(+Class)

Set the class of the module. See module_property/2.