31 lines
597 B
Rust
31 lines
597 B
Rust
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//@ known-bug: rust-lang/rust#129214
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//@ compile-flags: -Zvalidate-mir -Copt-level=3 --crate-type=lib
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trait to_str {}
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trait map<T> {
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fn map<U, F>(&self, f: F) -> Vec<U>
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where
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F: FnMut(&Box<usize>) -> U;
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}
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impl<T> map<T> for Vec<T> {
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fn map<U, F>(&self, mut f: F) -> Vec<U>
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where
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F: FnMut(&T) -> U,
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{
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let mut r = Vec::new();
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for i in self {
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r.push(f(i));
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}
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r
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}
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}
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fn foo<U, T: map<U>>(x: T) -> Vec<String> {
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x.map(|_e| "hi".to_string())
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}
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pub fn main() {
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assert_eq!(foo(vec![1]), ["hi".to_string()]);
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}
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