31 lines
1.1 KiB
Rust
31 lines
1.1 KiB
Rust
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// Test that `...X` range-to patterns are syntactically invalid.
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//
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// See https://github.com/rust-lang/rust/pull/67258#issuecomment-565656155
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// for the reason why. To summarize, we might want to introduce `...expr` as
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// an expression form for splatting (or "untupling") in an expression context.
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// While there is no syntactic ambiguity with `...X` in a pattern context,
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// there's a potential confusion factor here, and we would prefer to keep patterns
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// and expressions in-sync. As such, we do not allow `...X` in patterns either.
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fn main() {}
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#[cfg(FALSE)]
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fn syntax() {
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match scrutinee {
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...X => {} //~ ERROR range-to patterns with `...` are not allowed
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...0 => {} //~ ERROR range-to patterns with `...` are not allowed
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...'a' => {} //~ ERROR range-to patterns with `...` are not allowed
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...0.0f32 => {} //~ ERROR range-to patterns with `...` are not allowed
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}
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}
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fn syntax2() {
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macro_rules! mac {
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($e:expr) => {
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let ...$e; //~ ERROR range-to patterns with `...` are not allowed
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}
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}
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mac!(0);
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}
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