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now_you_see_me

This example illustrates that the implementation of dynamic predicates must ensure that retracting all local clauses for an inherited dynamic predicate restores the visibility of any inherited definition. This also have direct consequences for the implementation and optimization of (^^)/1 calls. For more information on this example, please see the comments in the example source files. The example is inspired by the "Now You See Me" movie, whose main characters are four stage magicians known as the "Four Horsemen".

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Start by loading the example:

logtalk_load(now_you_see_me(loader)).

Show all the horseman on stage:

stage::list.

<!-- danny merritt henley jack

true. -->

Hide the four horseman:

magic::hide.

Confirm that all of them are hiding:

<!-- true. -->

stage::list.

<!-- true. -->

Again show all the horseman on stage:

magic::show.

<!-- true. -->

List the horseman now again on stage:

stage::list.

<!-- danny merritt henley jack

true. -->