mirror of https://github.com/rust-lang/rust.git
49 lines
1.3 KiB
Rust
49 lines
1.3 KiB
Rust
// Test that macros can be defined in the labeled block. This should not trigger an error about
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// statements not being allowed in that position, and should of course work as expected.
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//@ run-pass
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#![allow(incomplete_features)]
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#![feature(loop_match)]
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enum State {
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A,
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B,
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C,
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}
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fn main() {
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let mut state = State::A;
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#[loop_match]
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'a: loop {
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state = 'blk: {
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macro_rules! const_continue {
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($e:expr) => {
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#[const_continue]
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break 'blk $e;
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};
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}
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match state {
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State::A => {
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const_continue!(State::B);
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}
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State::B => {
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// Without special logic, the compiler believes this is a
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// reassignment to an immutable variable because of the
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// `loop`. So this tests that local variables work.
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let _a = 0;
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if true {
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const_continue!(State::C);
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} else {
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const_continue!(State::A);
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}
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}
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State::C => break 'a,
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}
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};
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}
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assert!(matches!(state, State::C))
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}
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