39 lines
1.3 KiB
Rust
39 lines
1.3 KiB
Rust
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// Copyright 2018 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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// In expression, `&a..=b` is treated as `(&a)..=(b)` and `box a..=b` is
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// `(box a)..=(b)`. In a pattern, however, `&a..=b` means `&(a..=b)`. This may
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// lead to confusion.
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//
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// We are going to disallow `&a..=b` and `box a..=b` in a pattern. However, the
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// older ... syntax is still allowed as a stability guarantee.
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#![feature(box_patterns)]
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pub fn main() {
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match &12 {
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&0...9 => {}
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&10..=15 => {}
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//~^ ERROR the range pattern here has ambiguous interpretation
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//~^^ HELP add parentheses to clarify the precedence
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&(16..=20) => {}
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_ => {}
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}
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match Box::new(12) {
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box 0...9 => {}
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box 10..=15 => {}
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//~^ ERROR the range pattern here has ambiguous interpretation
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//~^^ HELP add parentheses to clarify the precedence
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box (16..=20) => {}
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_ => {}
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}
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}
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