41 lines
771 B
Rust
41 lines
771 B
Rust
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// check-pass
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// compile-flags: -Ztrait-solver=next
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trait Foo {
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type Gat<'a>
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where
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Self: 'a;
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fn bar(&self) -> Self::Gat<'_>;
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}
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enum Option<T> {
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Some(T),
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None,
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}
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impl<T> Option<T> {
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fn as_ref(&self) -> Option<&T> {
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match self {
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Option::Some(t) => Option::Some(t),
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Option::None => Option::None,
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}
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}
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fn map<U>(self, f: impl FnOnce(T) -> U) -> Option<U> {
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match self {
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Option::Some(t) => Option::Some(f(t)),
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Option::None => Option::None,
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}
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}
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}
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impl<T: Foo + 'static> Foo for Option<T> {
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type Gat<'a> = Option<<T as Foo>::Gat<'a>> where Self: 'a;
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fn bar(&self) -> Self::Gat<'_> {
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self.as_ref().map(Foo::bar)
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}
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}
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fn main() {}
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