69 lines
1.5 KiB
Rust
69 lines
1.5 KiB
Rust
// Copyright 2014 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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#![allow(unknown_features)]
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#![feature(box_syntax)]
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fn match_on_local() {
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let mut foo: Option<Box<_>> = Some(box 5);
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match foo {
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None => {},
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Some(x) => {
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foo = Some(x);
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}
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}
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println!("'{}'", foo.unwrap());
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}
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fn match_on_arg(mut foo: Option<Box<i32>>) {
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match foo {
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None => {}
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Some(x) => {
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foo = Some(x);
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}
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}
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println!("'{}'", foo.unwrap());
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}
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fn match_on_binding() {
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match Some(Box::new(7)) {
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mut foo => {
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match foo {
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None => {},
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Some(x) => {
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foo = Some(x);
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}
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}
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println!("'{}'", foo.unwrap());
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}
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}
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}
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fn match_on_upvar() {
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let mut foo: Option<Box<_>> = Some(box 8);
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let f = move|| {
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match foo {
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None => {},
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Some(x) => {
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foo = Some(x);
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}
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}
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println!("'{}'", foo.unwrap());
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};
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f();
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}
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fn main() {
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match_on_local();
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match_on_arg(Some(box 6));
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match_on_binding();
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match_on_upvar();
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}
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