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// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// ignore-pretty - token trees can't pretty print
macro_rules! myfn {
( $f:ident, ( $( $x:ident ),* ), $body:block ) => (
fn $f( $( $x : isize),* ) -> isize $body
)
}
myfn!(add, (a,b), { return a+b; } );
pub fn main() {
macro_rules! mylet {
($x:ident, $val:expr) => (
let $x = $val;
)
}
mylet!(y, 8*2);
assert_eq!(y, 16);
myfn!(mult, (a,b), { a*b } );
assert_eq!(mult(2, add(4,4)), 16);
macro_rules! actually_an_expr_macro {
() => ( 16 )
}
assert_eq!({ actually_an_expr_macro!() }, 16);
}
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