Byrd box tracing model

Author(s): Francisco Bueno.

This module can be used to spy predicates in a program. Spying means here to display messages at the call, exit, fail and redo ports of goals for the predicate spied.

In order to spy a predicate using this module a program expansion has to be performed on the program module defining the predicate. This is achieved by the byrdbox package.

This library is a programming exercise in CIAO expansion packages. It is meanly intended as an auxiliary library for library(tracing).

Usage and interface

Library usage:
:- use_package(byrdbox).
in the program module defining the code to be spied; or
:- use_module(library(byrdbox/byrd)).
to call the predicates exported by this module.
Exports:
- Predicates:
  spy/1, nospy/1, trace/1, trace0/1.

Documentation on exports

PREDICATEspy/1

spy(M:F/A)

Turns spying of predicate F/A in module M on. Declarations of the form spy(F/A) (where M is implicitly taken as the module where the declaration appears) can also be used, as long as the byrdbox package is included.

PREDICATEnospy/1

nospy(M:F/A)

Turns spying of predicate F/A in module M off.

PREDICATEtrace/1

trace(Goal)

Displays messages at the ports of Goal, as long as spying is on for its predicate. Meta-predicate with arguments: trace(goal).

PREDICATEtrace0/1

trace0(Goal)

Displays messages at the ports of Goal. Meta-predicate with arguments: trace0(goal).

Documentation on imports

This module has the following direct dependencies:

System library modules:
datafacts_rt, messages.
Internal (engine) modules:
term_basic, arithmetic, atomic_basic, basiccontrol, exceptions, term_compare, term_typing, debugger_support, basic_props, hiord_rt, internals.
Packages:
prelude, initial, condcomp, assertions, assertions/assertions_basic, datafacts.