27 lines
577 B
Rust
27 lines
577 B
Rust
#![feature(min_specialization)]
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use std::fmt::{self, Display};
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pub enum Cow<'a, B: ?Sized + 'a, O = <B as ToOwned>::Owned>
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where
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B: ToOwned,
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{
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Borrowed(&'a B),
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Owned(O),
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}
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impl ToString for Cow<'_, str> {
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fn to_string(&self) -> String {
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String::new()
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}
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}
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impl<B: ?Sized> Display for Cow<'_, B> {
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//~^ ERROR: the trait bound `B: Clone` is not satisfied [E0277]
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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//~^ ERROR: the trait bound `B: Clone` is not satisfied [E0277]
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write!(f, "foo")
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}
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}
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fn main() {}
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