rust/tests/ui/coercion/coerce-unify-return.rs
2024-02-16 20:02:50 +00:00

20 lines
525 B
Rust

//@ run-pass
// Check that coercions unify the expected return type of a polymorphic
// function call, instead of leaving the type variables as they were.
//@ pretty-expanded FIXME #23616
struct Foo;
impl Foo {
fn foo<T>(self, x: T) -> Option<T> { Some(x) }
}
pub fn main() {
let _: Option<fn()> = Some(main);
let _: Option<fn()> = Foo.foo(main);
// The same two cases, with implicit type variables made explicit.
let _: Option<fn()> = Some::<_>(main);
let _: Option<fn()> = Foo.foo::<_>(main);
}