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request_notification(++Name, ++Pred)
Requests that a predicate be called when an option changes
- Name
- Name of the option
- Pred
- Predicate to call
Description
Specifies that Pred(Name, OldValue, NewValue) should be called whenever
the value of the option Name is changed. OldValue is the old value of
the option that has just been replaced and NewValue is the new value that
has just been assigned. Pred should not modify OldValue or NewValue in
any way, as this may interfere with other notification predicates. Note
also that any choice points left by the call to Pred are pruned upon
success.
Modules
This predicate is sensitive to its module context (tool predicate, see @/2).
See Also
register_option / 3, set_option / 2