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|
// Needed for `type Y = impl Trait<_>` and `type B = _;`
#![feature(associated_type_defaults)]
#![feature(type_alias_impl_trait)]
// This test checks that it is not possible to enable global type
// inference by using the `_` type placeholder.
fn test() -> _ { 5 }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
fn test2() -> (_, _) { (5, 5) }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
static TEST3: _ = "test";
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
static TEST4: _ = 145;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
static TEST5: (_, _) = (1, 2);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
fn test6(_: _) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn test6_b<T>(_: _, _: T) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn test6_c<T, K, L, A, B>(_: _, _: (T, K, L, A, B)) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn test7(x: _) { let _x: usize = x; }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn test8(_f: fn() -> _) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
//~^^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
struct Test9;
impl Test9 {
fn test9(&self) -> _ { () }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
fn test10(&self, _x : _) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
}
fn test11(x: &usize) -> &_ {
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
&x
}
unsafe fn test12(x: *const usize) -> *const *const _ {
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
&x
}
impl Clone for Test9 {
fn clone(&self) -> _ { Test9 }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn clone_from(&mut self, other: _) { *self = Test9; }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
}
struct Test10 {
a: _,
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for structs
b: (_, _),
}
pub fn main() {
static A = 42;
//~^ ERROR missing type for `static` item
static B: _ = 42;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
static C: Option<_> = Some(42);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
fn fn_test() -> _ { 5 }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
fn fn_test2() -> (_, _) { (5, 5) }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
static FN_TEST3: _ = "test";
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
static FN_TEST4: _ = 145;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
static FN_TEST5: (_, _) = (1, 2);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for static variables
fn fn_test6(_: _) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn fn_test7(x: _) { let _x: usize = x; }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn fn_test8(_f: fn() -> _) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
//~^^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
struct FnTest9;
impl FnTest9 {
fn fn_test9(&self) -> _ { () }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
fn fn_test10(&self, _x : _) { }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
}
impl Clone for FnTest9 {
fn clone(&self) -> _ { FnTest9 }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn clone_from(&mut self, other: _) { *self = FnTest9; }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
}
struct FnTest10 {
a: _,
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for structs
b: (_, _),
}
fn fn_test11(_: _) -> (_, _) { panic!() }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
//~| ERROR type annotations needed
fn fn_test12(x: i32) -> (_, _) { (x, x) }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
fn fn_test13(x: _) -> (i32, _) { (x, x) }
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
}
trait T {
fn method_test1(&self, x: _);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn method_test2(&self, x: _) -> _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn method_test3(&self) -> _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn assoc_fn_test1(x: _);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn assoc_fn_test2(x: _) -> _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
fn assoc_fn_test3() -> _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for functions
}
struct BadStruct<_>(_);
//~^ ERROR expected identifier, found reserved identifier `_`
//~| ERROR the placeholder `_` is not allowed within types on item signatures for structs
trait BadTrait<_> {}
//~^ ERROR expected identifier, found reserved identifier `_`
impl BadTrait<_> for BadStruct<_> {}
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for implementations
fn impl_trait() -> impl BadTrait<_> {
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for opaque types
unimplemented!()
}
struct BadStruct1<_, _>(_);
//~^ ERROR expected identifier, found reserved identifier `_`
//~| ERROR expected identifier, found reserved identifier `_`
//~| ERROR the name `_` is already used
//~| ERROR the placeholder `_` is not allowed within types on item signatures for structs
struct BadStruct2<_, T>(_, T);
//~^ ERROR expected identifier, found reserved identifier `_`
//~| ERROR the placeholder `_` is not allowed within types on item signatures for structs
type X = Box<_>;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for type aliases
struct Struct;
trait Trait<T> {}
impl Trait<usize> for Struct {}
type Y = impl Trait<_>;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for opaque types
fn foo() -> Y {
Struct
}
trait Qux {
type A;
type B = _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for associated types
const C: _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for constants
const D: _ = 42;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for constants
// type E: _; // FIXME: make the parser propagate the existence of `B`
type F: std::ops::Fn(_);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for associated types
}
impl Qux for Struct {
type A = _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for associated types
type B = _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for associated types
const C: _;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for constants
//~| ERROR associated constant in `impl` without body
const D: _ = 42;
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for constants
}
fn map<T>(_: fn() -> Option<&'static T>) -> Option<T> {
None
}
fn value() -> Option<&'static _> {
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
Option::<&'static u8>::None
}
const _: Option<_> = map(value);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for constants
fn evens_squared(n: usize) -> _ {
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for return types
(1..n).filter(|x| x % 2 == 0).map(|x| x * x)
}
const _: _ = (1..10).filter(|x| x % 2 == 0).map(|x| x * x);
//~^ ERROR the placeholder `_` is not allowed within types on item signatures for constants
|
