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Diffstat (limited to 'src/test/ui/variance/variance-trait-matching.rs')
-rw-r--r-- | src/test/ui/variance/variance-trait-matching.rs | 38 |
1 files changed, 0 insertions, 38 deletions
diff --git a/src/test/ui/variance/variance-trait-matching.rs b/src/test/ui/variance/variance-trait-matching.rs deleted file mode 100644 index b4efee7d6..000000000 --- a/src/test/ui/variance/variance-trait-matching.rs +++ /dev/null @@ -1,38 +0,0 @@ -#![allow(dead_code)] - -// Get<T> is covariant in T -trait Get<T> { - fn get(&self) -> T; -} - -struct Cloner<T:Clone> { - t: T -} - -impl<T:Clone> Get<T> for Cloner<T> { - fn get(&self) -> T { - self.t.clone() - } -} - -fn get<'a, G>(get: &G) -> i32 - where G : Get<&'a i32> -{ - // This fails to type-check because, without variance, we can't - // use `G : Get<&'a i32>` as evidence that `G : Get<&'b i32>`, - // even if `'a : 'b`. - pick(get, &22) //~ ERROR explicit lifetime required in the type of `get` [E0621] -} - -fn pick<'b, G>(get: &'b G, if_odd: &'b i32) -> i32 - where G : Get<&'b i32> -{ - let v = *get.get(); - if v % 2 != 0 { v } else { *if_odd } -} - -fn main() { - let x = Cloner { t: &23 }; - let y = get(&x); - assert_eq!(y, 23); -} |