15 lines
580 B
Rust
15 lines
580 B
Rust
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#[macro_export]
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macro_rules! helper {
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// Use `:tt` instead of `:ident` so that we don't get a `None`-delimited group
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($first:tt) => {
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pub fn foo<T>() {
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// The span of `$first` comes from another file,
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// so the expression `1 + $first` ends up with an
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// 'invalid' span that starts and ends in different files.
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// We use the `respan!` macro to give all tokens the same
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// `SyntaxContext`, so that the parser will try to merge the spans.
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respan::respan!(let a = 1 + $first;);
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}
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}
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}
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