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#![feature(associated_type_defaults)]
struct S;
mod method {
trait A {
fn a(&self) { }
}
pub trait B {
fn b(&self) { }
}
pub trait C: A + B {
fn c(&self) { }
}
impl A for ::S {}
impl B for ::S {}
impl C for ::S {}
}
mod assoc_const {
trait A {
const A: u8 = 0;
}
pub trait B {
const B: u8 = 0;
}
pub trait C: A + B {
const C: u8 = 0;
}
impl A for ::S {}
impl B for ::S {}
impl C for ::S {}
}
mod assoc_ty {
trait A {
type A = u8;
}
pub trait B {
type B = u8;
}
pub trait C: A + B {
type C = u8;
}
impl A for ::S {}
impl B for ::S {}
impl C for ::S {}
}
fn check_method() {
// A is private
// B is pub, not in scope
// C : A + B is pub, in scope
use method::C;
// Methods, method call
// a, b, c are resolved as trait items, their traits need to be in scope
S.a(); //~ ERROR no method named `a` found
S.b(); //~ ERROR no method named `b` found
S.c(); // OK
// a, b, c are resolved as inherent items, their traits don't need to be in scope
let c = &S as &dyn C;
c.a(); //~ ERROR method `a` is private
c.b(); // OK
c.c(); // OK
// Methods, UFCS
// a, b, c are resolved as trait items, their traits need to be in scope
S::a(&S);
//~^ ERROR no function or associated item named `a` found
S::b(&S);
//~^ ERROR no function or associated item named `b` found
S::c(&S); // OK
// a, b, c are resolved as inherent items, their traits don't need to be in scope
<dyn C>::a(&S); //~ ERROR method `a` is private
<dyn C>::b(&S); // OK
C::c(&S); // OK
}
fn check_assoc_const() {
// A is private
// B is pub, not in scope
// C : A + B is pub, in scope
use assoc_const::C;
// Associated constants
// A, B, C are resolved as trait items, their traits need to be in scope
S::A; //~ ERROR no associated item named `A` found
S::B; //~ ERROR no associated item named `B` found
S::C; // OK
// A, B, C are resolved as inherent items, their traits don't need to be in scope
<dyn C>::A; //~ ERROR associated constant `A` is private
//~^ ERROR the trait `assoc_const::C` cannot be made into an object
<dyn C>::B; // ERROR the trait `assoc_const::C` cannot be made into an object
C::C; // OK
}
fn check_assoc_ty<T: assoc_ty::C>() {
// A is private
// B is pub, not in scope
// C : A + B is pub, in scope
use assoc_ty::C;
// Associated types
// A, B, C are resolved as trait items, their traits need to be in scope, not implemented yet
let _: S::A; //~ ERROR ambiguous associated type
let _: S::B; //~ ERROR ambiguous associated type
let _: S::C; //~ ERROR ambiguous associated type
// A, B, C are resolved as inherent items, their traits don't need to be in scope
let _: T::A; //~ ERROR associated type `A` is private
let _: T::B; // OK
let _: T::C; // OK
// Associated types, bindings
let _: dyn assoc_ty::B<
B = u8, // OK
>;
let _: dyn C<
A = u8, //~ ERROR associated type `A` is private
B = u8, // OK
C = u8, // OK
>;
}
fn main() {}
|
