33 lines
930 B
Rust
33 lines
930 B
Rust
// Copyright 2016 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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// `expr?` expands to:
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//
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// match expr {
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// Ok(val) => val,
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// Err(err) => return Err(From::from(err)),
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// }
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//
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// This test verifies that the expansion is hygienic, i.e. it's not affected by other `val` and
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// `err` bindings that may be in scope.
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use std::num::ParseIntError;
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fn main() {
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assert_eq!(parse(), Ok(1));
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}
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fn parse() -> Result<i32, ParseIntError> {
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const val: char = 'a';
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const err: char = 'b';
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Ok("1".parse::<i32>()?)
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}
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