38 lines
870 B
Rust
38 lines
870 B
Rust
//@ known-bug: #130956
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mod impl_trait_mod {
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use super::*;
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pub type OpaqueBlock = impl Trait;
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pub type OpaqueIf = impl Trait;
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pub struct BlockWrapper(OpaqueBlock);
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pub struct IfWrapper(pub OpaqueIf);
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pub fn if_impl() -> Parser<OpaqueIf> {
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bind(option(block()), |_| block())
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}
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}
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use impl_trait_mod::*;
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pub trait Trait {
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type Assoc;
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}
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pub struct Parser<P>(P);
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pub struct Bind<P, F>(P, F);
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impl<P, F> Trait for Bind<P, F> { type Assoc = (); }
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impl Trait for BlockWrapper { type Assoc = (); }
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impl Trait for IfWrapper { type Assoc = (); }
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pub fn block() -> Parser<BlockWrapper> {
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loop {}
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}
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pub fn option<P: Trait>(arg: Parser<P>) -> Parser<impl Trait> {
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bind(arg, |_| block())
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}
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fn bind<P: Trait, P2, F: Fn(P::Assoc) -> Parser<P2>>(_: Parser<P>, _: F) -> Parser<Bind<P, F>>
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{ loop {} }
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fn main() {
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if_impl().0;
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}
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