29 lines
608 B
Rust
29 lines
608 B
Rust
trait MyFn<Arg> {
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type Output;
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fn call(&self, arg: Arg) -> Self::Output;
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}
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struct Wrap<F>(F);
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impl<A, B, F> MyFn<A> for Wrap<F>
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where
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F: Fn(A) -> B
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{
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type Output = B;
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fn call(&self, arg: A) -> Self::Output {
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(self.0)(arg)
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}
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}
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struct A;
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fn test() -> impl for<'a> MyFn<&'a A, Output=impl Iterator + 'a> {
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//~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet
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Wrap(|a| Some(a).into_iter())
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//~^ ERROR implementation of `FnOnce` is not general enough
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//~| ERROR implementation of `FnOnce` is not general enough
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}
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fn main() {}
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