mirror of
https://github.com/rust-lang/rust.git
synced 2024-12-11 08:05:12 +00:00
30 lines
670 B
Rust
30 lines
670 B
Rust
trait Foo {}
|
|
|
|
impl<F> Foo for F where F: Fn(&i32) -> &i32 {}
|
|
|
|
fn take_foo(_: impl Foo) {}
|
|
|
|
fn main() {
|
|
take_foo(|a| a);
|
|
//~^ ERROR implementation of `FnOnce` is not general enough
|
|
//~| ERROR mismatched types
|
|
take_foo(|a: &i32| a);
|
|
//~^ ERROR lifetime may not live long enough
|
|
//~| ERROR mismatched types
|
|
take_foo(|a: &i32| -> &i32 { a });
|
|
//~^ ERROR lifetime may not live long enough
|
|
//~| ERROR mismatched types
|
|
|
|
// OK
|
|
take_foo(identity(|a| a));
|
|
take_foo(identity(|a: &i32| a));
|
|
take_foo(identity(|a: &i32| -> &i32 { a }));
|
|
|
|
fn identity<F>(t: F) -> F
|
|
where
|
|
F: Fn(&i32) -> &i32,
|
|
{
|
|
t
|
|
}
|
|
}
|