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24 lines
502 B
Rust
24 lines
502 B
Rust
//@ run-pass
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#![allow(unused_macro_rules)]
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/// A compile-time map from identifiers to arbitrary (heterogeneous) expressions
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macro_rules! ident_map {
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( $name:ident = { $($key:ident => $e:expr,)* } ) => {
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macro_rules! $name {
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$(
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( $key ) => { $e };
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)*
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// Empty invocation expands to nothing. Needed when the map is empty.
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() => {};
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}
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};
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}
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ident_map!(my_map = {
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main => 0,
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});
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fn main() {
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my_map!(main);
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}
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