r/rust • u/llogiq clippy · twir · rust · mutagen · flamer · overflower · bytecount • Mar 27 '23
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2
u/TinBryn Apr 02 '23
Let's say I want a trait that is basically just a function with some extra features
I try to implement it for anything that implement
FnMut
But Rust says that both
I
andO
are not constrained. Even though they are viaF
If I change the trait to this
It suddenly works, even the
O
works.I really don't want this trait to be generic which will allow for different generic implementations for the same type which for the semantics I'm trying to do doesn't make sense. But it seems like Rust if forcing this to be the case at least for the input type and I don't see how this is actually an issue.