spy/0 — enable spy points
spy/1 — sets a spy point
nospy/0 — removes all spy points
nospy/1 — removes a spy point
spy Name/Arity nospy Name/Arity nospy spy(Module : Name/Arity) nospy(Module : Name/Arity)
spy/1 places a spy point on the procedure name
nospy/1 removes a specific spy point, while
nospy/0 removes all spy points that are currently set. During consult or reconsult, all spy points are disabled, and spy points on predicates which are consulted or reconsulted are removed.
spy/0 re-enables spy points which have been disabled (e.g., those which were not removed, but were disabled during a reconsult).