51 lines
902 B
Rust
51 lines
902 B
Rust
// check-pass
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use std::ops::Add;
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trait Trait<T> {
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fn get(self) -> T;
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}
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struct Holder<T>(T);
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impl<T> Trait<T> for Holder<T> {
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fn get(self) -> T {
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self.0
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}
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}
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enum Either<L, R> {
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Left(L),
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Right(R),
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}
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impl<L, R> Either<L, R> {
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fn converge<T>(self) -> T
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where
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L: Trait<T>,
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R: Trait<T>,
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{
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match self {
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Either::Left(val) => val.get(),
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Either::Right(val) => val.get(),
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}
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}
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}
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fn add_generic<A: Add<B>, B>(
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lhs: A,
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rhs: B,
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) -> Either<impl Trait<<A as Add<B>>::Output>, impl Trait<<A as Add<B>>::Output>> {
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if true { Either::Left(Holder(lhs + rhs)) } else { Either::Right(Holder(lhs + rhs)) }
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}
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fn add_one(
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value: u32,
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) -> Either<impl Trait<<u32 as Add<u32>>::Output>, impl Trait<<u32 as Add<u32>>::Output>> {
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add_generic(value, 1u32)
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}
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pub fn main() {
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add_one(3).converge();
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}
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