rust/src/test/run-pass/in-band-lifetimes.rs
2018-12-25 21:08:33 -07:00

95 lines
2.3 KiB
Rust

#![allow(warnings)]
#![feature(in_band_lifetimes)]
fn foo(x: &'x u8) -> &'x u8 { x }
fn foo2(x: &'a u8, y: &u8) -> &'a u8 { x }
fn check_in_band_can_be_late_bound() {
let _: for<'x> fn(&'x u8, &u8) -> &'x u8 = foo2;
}
struct ForInherentNoParams;
impl ForInherentNoParams {
fn foo(x: &'a u32, y: &u32) -> &'a u32 { x }
}
struct X<'a>(&'a u8);
impl<'a> X<'a> {
fn inner(&self) -> &'a u8 {
self.0
}
fn same_lifetime_as_parameter(&mut self, x: &'a u8) {
self.0 = x;
}
}
impl X<'b> {
fn inner_2(&self) -> &'b u8 {
self.0
}
fn reference_already_introduced_in_band_from_method_with_explicit_binders<'a>(
&'b self, x: &'a u32
) {}
}
struct Y<T>(T);
impl Y<&'a u8> {
fn inner(&self) -> &'a u8 {
self.0
}
}
trait MyTrait<'a> {
fn my_lifetime(&self) -> &'a u8;
fn any_lifetime() -> &'b u8;
fn borrowed_lifetime(&'b self) -> &'b u8;
fn default_impl(&self, x: &'b u32, y: &u32) -> &'b u32 { x }
fn in_band_def_explicit_impl(&self, x: &'b u8);
}
impl MyTrait<'a> for Y<&'a u8> {
fn my_lifetime(&self) -> &'a u8 { self.0 }
fn any_lifetime() -> &'b u8 { &0 }
fn borrowed_lifetime(&'b self) -> &'b u8 { &*self.0 }
fn in_band_def_explicit_impl<'b>(&self, x: &'b u8) {}
}
fn test_hrtb_defined_lifetime_where<F>(_: F) where for<'a> F: Fn(&'a u8) {}
fn test_hrtb_defined_lifetime_polytraitref<F>(_: F) where F: for<'a> Fn(&'a u8) {}
fn reference_in_band_from_locals(x: &'test u32) -> &'test u32 {
let y: &'test u32 = x;
y
}
fn in_generics_in_band<T: MyTrait<'a>>(x: &T) {}
fn where_clause_in_band<T>(x: &T) where T: MyTrait<'a> {}
fn impl_trait_in_band(x: &impl MyTrait<'a>) {}
// Tests around using in-band lifetimes within existential traits.
trait FunkyTrait<'a> { }
impl<'a, T> FunkyTrait<'a> for T { }
fn existential_impl_trait_in_band_outlives(x: &'a u32) -> impl ::std::fmt::Debug + 'a {
x
}
fn existential_impl_trait_in_band_param(x: &'a u32) -> impl FunkyTrait<'a> {
x
}
fn existential_impl_trait_in_band_param_static(x: &'a u32) -> impl FunkyTrait<'static> + 'a {
x
}
fn existential_impl_trait_in_band_param_outlives(x: &'a u32) -> impl FunkyTrait<'a> + 'a {
x
}
fn existential_impl_trait_in_band_higher_ranked(x: &'a u32) -> impl for<'b> FunkyTrait<'b> + 'a {
x
}
fn main() {}