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dynamic ++SpecList

Declares the procedures specified by SpecList as dynamic.
SpecList
Sequence of expressions of the form Atom/Integer.

Description

Declare the procedures specified by SpecList as dynamic procedures. This has to be done before the procedure is defined.

To change a static procedure to a dynamic one it must first be abolished.

If the procedure was already dynamic Error 64 is raised. The default error handler erases all existing clauses and succeeds. This is useful for recompiling files with dynamic declarations, but it can be redefined if desired.

Modes and Determinism

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Exceptions

(4) instantiation fault
SpecList is not instantiated.
(5) type error
SpecList is instantiated, but not to a sequence of expressions of the form Atom/Integer.
(64) procedure already dynamic
SpecList is already dynamic.
(65) procedure already defined
SpecList is already defined.

Examples

Success:
     [eclipse]: pred(a/1).
     no.
     [eclipse]: dynamic a/1.
     yes.
     [eclipse]: pred(a/1).
     in eclipse: dynamic prolog local debugged stopped traceable
     yes.
     [eclipse]: a(X).
     no (more) solution.
Error:
     dynamic X.                 (Error 4).
     dynamic a.                 (Error 5).
     dynamic a/1, a/1.          (Error 64). % succeeds
     get_flag(p/0,type,user),
     dynamic p/0.               (Error 65).

See Also

is_dynamic / 1