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23 lines
493 B
Rust
23 lines
493 B
Rust
//@ run-pass
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macro_rules! higher_order {
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(subst $lhs:tt => $rhs:tt) => ({
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macro_rules! anon { $lhs => $rhs }
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anon!(1_usize, 2_usize, "foo")
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});
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}
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macro_rules! outer {
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($x:expr; $fragment:ident) => {
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macro_rules! inner { ($y:$fragment) => { $x + $y } }
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}
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}
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fn main() {
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let val = higher_order!(subst ($x:expr, $y:expr, $foo:expr) => (($x + $y, $foo)));
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assert_eq!(val, (3, "foo"));
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outer!(2; expr);
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assert_eq!(inner!(3), 5);
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}
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