mirror of https://github.com/rust-lang/rust
85 lines
1.8 KiB
Rust
85 lines
1.8 KiB
Rust
//@ check-pass
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#![allow(dead_code)]
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#![allow(unused_assignments)]
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#![allow(unused_variables)]
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#![feature(type_alias_impl_trait)]
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fn main() {
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assert_eq!(foo().to_string(), "foo");
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assert_eq!(bar1().to_string(), "bar1");
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assert_eq!(bar2().to_string(), "bar2");
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let mut x = bar1();
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x = bar2();
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assert_eq!(my_iter(42u8).collect::<Vec<u8>>(), vec![42u8]);
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}
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use defining_use_scope::*;
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mod defining_use_scope {
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// single definition
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pub type Foo = impl std::fmt::Display;
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pub fn foo() -> Foo {
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"foo"
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}
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// two definitions
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pub type Bar = impl std::fmt::Display;
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pub fn bar1() -> Bar {
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"bar1"
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}
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pub fn bar2() -> Bar {
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"bar2"
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}
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pub type MyIter<T> = impl Iterator<Item = T>;
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pub fn my_iter<T>(t: T) -> MyIter<T> {
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std::iter::once(t)
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}
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fn my_iter2<T>(t: T) -> MyIter<T> {
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std::iter::once(t)
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}
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// param names should not have an effect!
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fn my_iter3<U>(u: U) -> MyIter<U> {
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std::iter::once(u)
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}
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// param position should not have an effect!
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fn my_iter4<U, V>(_: U, v: V) -> MyIter<V> {
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std::iter::once(v)
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}
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// param names should not have an effect!
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type MyOtherIter<T> = impl Iterator<Item = T>;
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fn my_other_iter<U>(u: U) -> MyOtherIter<U> {
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std::iter::once(u)
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}
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trait Trait {}
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type GenericBound<'a, T: Trait + 'a> = impl Sized + 'a;
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fn generic_bound<'a, T: Trait + 'a>(t: T) -> GenericBound<'a, T> {
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t
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}
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mod pass_through {
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pub type Passthrough<T: 'static> = impl Sized + 'static;
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fn define_passthrough<T: 'static>(t: T) -> Passthrough<T> {
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t
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}
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}
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fn use_passthrough(x: pass_through::Passthrough<u32>) -> pass_through::Passthrough<u32> {
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x
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}
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}
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