31 lines
571 B
Rust
31 lines
571 B
Rust
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// check-pass
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trait FnOnceForGenericRef<T>: FnOnce(&T) -> Self::FnOutput {
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type FnOutput;
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}
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impl<T, R, F: FnOnce(&T) -> R> FnOnceForGenericRef<T> for F {
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type FnOutput = R;
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}
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struct Data<T, D: FnOnceForGenericRef<T>> {
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value: Option<T>,
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output: Option<D::FnOutput>,
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}
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impl<T, D: FnOnceForGenericRef<T>> Data<T, D> {
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fn new(value: T, f: D) -> Self {
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let output = f(&value);
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Self {
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value: Some(value),
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output: Some(output),
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}
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}
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}
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fn test() {
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Data::new(String::new(), |_| {});
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}
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fn main() {}
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