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complements (restrict)

This folder contains an example that show how to use a category to explicitly complement an existing object compiled with the complements flag set to restrict. With this setting, a category can only add new functionality to the complemented object.

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

%versions

Start by loading the non-patched vault objects:

logtalk_load(complements_restrict(vaults)).

Open the my_vault vault using the correct password:

my_vault::open('!"#$%&/()=').

Any other password will be rejected. For example:

my_vault::open('abc123').

Now load the hacker complementing category:

logtalk_load(complements_restrict(hacker)).

Try the hacker replaced password and fail miserably:

my_vault::open('1234567890').

The correct, original, password is still the only one capable of opening the vault, despite the hacker messages:

my_vault::open('!"#$%&/()=').