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// Regression test for #130956
#![feature(type_alias_impl_trait)]
mod impl_trait_mod {
use super::*;
pub type OpaqueBlock = impl Trait;
//~^ ERROR unconstrained opaque type
pub type OpaqueIf = impl Trait;
pub struct BlockWrapper(OpaqueBlock);
pub struct IfWrapper(pub OpaqueIf);
pub fn if_impl() -> Parser<OpaqueIf> {
bind(option(block()), |_| block())
}
}
use impl_trait_mod::*;
pub trait Trait {
type Assoc;
}
pub struct Parser<P>(P);
pub struct Bind<P, F>(P, F);
impl<P, F> Trait for Bind<P, F> { type Assoc = (); }
impl Trait for BlockWrapper { type Assoc = (); }
impl Trait for IfWrapper { type Assoc = (); }
pub fn block() -> Parser<BlockWrapper> {
loop {}
}
pub fn option<P: Trait>(arg: Parser<P>) -> Parser<impl Trait> {
bind(arg, |_| block())
}
fn bind<P: Trait, P2, F: Fn(P::Assoc) -> Parser<P2>>(_: Parser<P>, _: F) -> Parser<Bind<P, F>>
{ loop {} }
fn main() {
if_impl().0;
}
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