| // Copyright 2015 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. |
| |
| macro_rules! pat_in { |
| ($p:pat in $e:expr) => {{ |
| let mut iter = $e.into_iter(); |
| while let $p = iter.next() {} |
| }} |
| } |
| |
| macro_rules! pat_if { |
| ($p:pat if $e:expr) => {{ |
| match Some(1u8) { |
| $p if $e => {}, |
| _ => {} |
| } |
| }} |
| } |
| |
| macro_rules! pat_bar { |
| ($p:pat | $p2:pat) => {{ |
| match Some(1u8) { |
| $p | $p2 => {}, |
| _ => {} |
| } |
| }} |
| } |
| |
| fn main() { |
| pat_in!(Some(_) in 0..10); |
| pat_if!(Some(x) if x > 0); |
| pat_bar!(Some(1u8) | None); |
| } |