Array repeat expressions with nested blocks do not recognize constants

[RalfJung]

I tried the following code:

pub fn make_vecs() -> [Vec<i32>; 5] {
    [{
        const C: Vec<i32> = Vec::new();
        C
    }; 5]
}

I thought this would be accepted, since C is a constant.
But it does get rejected, probably because of the surrounding curly braces.

This code may look unnatural, but it is the kind of code that arises from a macro-based implementation of anonymous/inline constants.
Cc @oli-obk

[oli-obk]

hmm... it feels odd to allow this, I mean it's pretty much the reason we have inline consts as a feature and allowing it would require special casing blocks just for this use case

[RalfJung]

That's fair, I cannot seem to come up with any reasonable way this would arise unless one tries to re-implement inline consts as a macro...