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lock(+Module)

Locks the access to the module Module.
Module
Atom.

Description

Used to forbid the access to the given module when not using its interface.

It is impossible to unlock a module locked with lock/1. However, a module locked using lock/2, can still be unlocked with unlock/2.

An error is raised (error 82) when trying to lock a locked module.

Modes and Determinism

Exceptions

(4) instantiation fault
Module is not instantiated.
(5) type error
Module is instantiated, but not to an atom.
(80) not a module
Module is not a module.
(82) trying to access a locked module
Trying to access a locked module Module.

Examples

Success:
     [eclipse]: [user].
      :- module(m).
      :- export p/0.
      p :- writeln(hello).
      user compiled 60 bytes in 0.00 seconds
     yes.
     [eclipse]: lock(m).
     yes.
     [eclipse]: module(m).
     trying to access a locked module in module(m)
     [eclipse]: import p/0 from m.
     yes.
     [eclipse]: call(p) @ m.
     trying to access a locked module in p
     [eclipse]: p.
     hello
     yes.
Error:
     lock(M).                   (Error 4).
     lock(1).                   (Error 5).
     lock(not_a_module).        (Error 80).
     lock(m), call(p) @ m.      (Error 82).



See Also

lock / 2, unlock / 2, get_module_info / 3