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_archive/rhai_engine/rhaibook/rust/modules/index.md

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+Modules
+=======
+
+{{#include ../../links.md}}
+
+Rhai allows organizing functionalities ([functions], both Rust-based and scripted, and
+[variables]) into independent _modules_.
+
+A module has the type `rhai::Module` and holds a collection of [functions], [variables], [type
+iterators] and sub-modules.
+
+It may contain entirely Rust functions, or it may encapsulate a Rhai script together with
+all the [functions] and [variables] defined by that script.
+
+Other scripts then load this module and use the [functions] and [variables] [exported][`export`].
+
+Alternatively, modules can be registered directly into an [`Engine`] and made available to scripts,
+either globally or under individual static module [_namespaces_][function namespaces].
+
+Modules can be disabled via the [`no_module`] feature.
+
+
+Usage Patterns
+--------------
+
+| Usage          |                API                |          Lookup          | Sub-modules? | Variables? |
+| -------------- | :-------------------------------: | :----------------------: | :----------: | :--------: |
+| Global module  | `Engine:: register_global_module` |       simple name        |   ignored    |    yes     |
+| Static module  | `Engine:: register_static_module` | namespace-qualified name |     yes      |    yes     |
+| Dynamic module |       [`import`] statement        | namespace-qualified name |     yes      |    yes     |