mirror of https://github.com/rust-lang/rust
21 lines
538 B
Rust
21 lines
538 B
Rust
macro_rules! arm {
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($pattern:pat => $block:block) => {
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$pattern => $block
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//~^ ERROR macro expansion ignores token `=>` and any following
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//~| NOTE the usage of `arm!` is likely invalid in pattern context
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//~| NOTE macros cannot expand to match arms
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};
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}
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fn main() {
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let x = Some(1);
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match x {
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Some(1) => {},
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arm!(None => {}),
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//~^ NOTE caused by the macro expansion here
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//~| ERROR `match` arm with no body
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Some(2) => {},
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_ => {},
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};
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}
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