43 lines
1.1 KiB
Markdown
43 lines
1.1 KiB
Markdown
Automatic Global Module
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=======================
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{{#include ../links.md}}
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When a [constant] is declared at global scope, it is added to a special [module] called `global`.
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[Functions] can access those [constants] via the special `global` [module].
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Naturally, the automatic `global` [module] is not available under [`no_function`] nor [`no_module`].
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```rust
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const CONSTANT = 42; // this constant is automatically added to 'global'
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{
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const INNER = 0; // this constant is not at global level
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} // <- it goes away here
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fn foo(x) {
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x *= global::CONSTANT; // ok! 'CONSTANT' exists in 'global'
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x * global::INNER // <- error: constant 'INNER' not found in 'global'
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}
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```
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Override `global`
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-----------------
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It is possible to _override_ the automatic global [module] by [importing][`import`] another [module]
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under the name `global`.
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```rust
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import "foo" as global; // import a module as 'global'
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const CONSTANT = 42; // this constant is NOT added to 'global'
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fn foo(x) {
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global::CONSTANT // <- error: constant 'CONSTANT' not found in 'global'
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}
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```
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