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// Test that we consider these two types completely equal:
//
// * `for<'a, 'b> fn(&'a u32, &'b u32)`
// * `for<'c> fn(&'c u32, &'c u32)`
//
// For a long time we considered these to be distinct types. But in fact they
// are equivalent, if you work through the implications of subtyping -- this is
// because:
//
// * `'c` can be the intersection of `'a` and `'b` (and there is always an intersection)
// * `'a` and `'b` can both be equal to `'c`
trait Trait {}
impl Trait for for<'a, 'b> fn(&'a u32, &'b u32) {}
impl Trait for for<'c> fn(&'c u32, &'c u32) {
//~^ ERROR conflicting implementations
//
// Note in particular that we do NOT get a future-compatibility warning
// here. This is because the new leak-check proposed in [MCP 295] does not
// "error" when these two types are equated.
//
// [MCP 295]: https://github.com/rust-lang/compiler-team/issues/295
}
fn main() {}
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