32 lines
549 B
Rust
32 lines
549 B
Rust
//@ run-pass
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macro_rules! myfn {
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( $f:ident, ( $( $x:ident ),* ), $body:block ) => (
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fn $f( $( $x : isize),* ) -> isize $body
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)
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}
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myfn!(add, (a,b), { return a+b; } );
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pub fn main() {
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macro_rules! mylet {
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($x:ident, $val:expr) => (
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let $x = $val;
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)
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}
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mylet!(y, 8*2);
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assert_eq!(y, 16);
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myfn!(mult, (a,b), { a*b } );
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assert_eq!(mult(2, add(4,4)), 16);
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macro_rules! actually_an_expr_macro {
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() => ( 16 )
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}
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assert_eq!({ actually_an_expr_macro!() }, 16);
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}
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