Variadic curry

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I'd like to write a variadic version of curry but every version I try gets rejected. Here's what seems like it should work:

func curry<A, each B, C>(
    _ f: @escaping (A, repeat each B) -> C
) -> (A) -> (repeat each B) -> C {
    { (a: A) ->  (repeat each B) -> C in
        { b in f(a, repeat each b) }
    }
}

I've played around with some other forms, my favorite error message so far is:

Cannot fully abstract a value of variadic function type 
'@Sendable (A, repeat each B) async -> C' 
because different contexts will not be able to reliably agree on a 
calling convention; try wrapping it in a struct

Which is the first I've seen of that.

Anyone have any advice?

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