31 lines
828 B
Rust
31 lines
828 B
Rust
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// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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macro_rules! pat_in {
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($p:pat in $e:expr) => {{
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let mut iter = $e.into_iter();
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while let $p = iter.next() {}
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}}
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}
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macro_rules! pat_if {
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($p:pat if $e:expr) => {{
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match Some(1u8) {
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$p if $e => {},
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_ => {}
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}
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}}
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}
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fn main() {
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pat_in!(Some(_) in 0..10);
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pat_if!(Some(x) if x > 0);
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}
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