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Diffstat (limited to '')
-rw-r--r-- | src/test/ui/issues/issue-55731.rs | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/src/test/ui/issues/issue-55731.rs b/src/test/ui/issues/issue-55731.rs new file mode 100644 index 000000000..7b4f4e2cd --- /dev/null +++ b/src/test/ui/issues/issue-55731.rs @@ -0,0 +1,52 @@ +use std::marker::PhantomData; + +trait DistributedIterator { + fn reduce(self) + where + Self: Sized, + { + unreachable!() + } +} + +trait DistributedIteratorMulti<Source> { + type Item; +} + +struct Connect<I>(PhantomData<fn(I)>); +impl<I: for<'a> DistributedIteratorMulti<&'a ()>> DistributedIterator for Connect<I> where {} + +struct Cloned<Source>(PhantomData<fn(Source)>); +impl<'a, Source> DistributedIteratorMulti<&'a Source> for Cloned<&'a Source> { + type Item = (); +} + +struct Map<I, F> { + i: I, + f: F, +} +impl<I: DistributedIteratorMulti<Source>, F, Source> DistributedIteratorMulti<Source> for Map<I, F> +where + F: A<<I as DistributedIteratorMulti<Source>>::Item>, +{ + type Item = (); +} + +trait A<B> {} + +struct X; +impl A<()> for X {} + +fn multi<I>(_reducer: I) +where + I: for<'a> DistributedIteratorMulti<&'a ()>, +{ + DistributedIterator::reduce(Connect::<I>(PhantomData)) +} + +fn main() { + multi(Map { //~ ERROR implementation of `DistributedIteratorMulti` is not general enough + i: Cloned(PhantomData), + f: X, + }); +} |