unload: Unload or reload modules

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Unload or reload modules

Description

Given a module which has been previously loaded and is assigned to an alias mod, box::unload(mod) unloads it; box::reload(mod) unloads and reloads it from its source. box::purge_cache() marks all modules as unloaded.

Usage

box::unload(mod)

box::reload(mod)

box::purge_cache()

Arguments

mod	a module object to be unloaded or reloaded

Details

Unloading a module causes it to be removed from the internal cache such that the next subsequent box::use declaration will reload the module from its source. box::reload unloads and reloads the specified modules and all its transitive module dependencies. box::reload is not merely a shortcut for calling box::unload followed by box::use, because box::unload only unloads the specified module itself, not any dependent modules.

Value

These functions are called for their side effect. They do not return anything.

Note

Any other references to the loaded modules remain unchanged, and will (usually) still work. Unloading and reloading modules is primarily useful for testing during development, and should not be used in production code: in particular, unloading may break other module references if the .on_unload hook unloaded any binary shared libraries which are still referenced.

These functions come with a few restrictions. box::unload attempts to detach names attached by the corresponding box::use call. box::reload attempts to re-attach these same names. This only works if the corresponding box::use declaration is located in the same scope. box::purge_cache only removes the internal cache of modules, it does not actually invalidate any module references or names attached from loaded modules.

box::unload will execute the .on_unload hook of the module, if it exists. box::reload will re-execute the .on_load hook of the module and of all dependent modules during loading (after executing the corresponding .on_unload hooks during unloading). box::purge_cache will execute any existing .on_unload hooks in all loaded modules.

See Also

box::use, module hooks

box documentation built on May 2, 2023, 9:14 a.m.