julia> struct A end julia> struct B end julia> struct C{AA,BB} a :: AA b :: BB end julia> v = Union{C{A,B}, C{B,B}}[C(A(), B()), C(B(),B())] 2-element Vector{Union{C{A, B}, C{B, B}}}: C{A, B}(A(), B()) C{B, B}(B(), B()) julia> map(identity, v) 2-element Vector{C{AA, B} w…

I doubt this solves your problem beyond this MWE, but this specific problem does not appear for v = C{Union{A,B}, B}[C(A(), B()), C(B(), B())]. Another (ugly) option is to preallocate your result with the desired type as in map!(identity, similar(v), v), but that’s annoying to maintain as I often us…

Map over vector with union eltype makes type-inference worse

General Usage

Benny April 12, 2023, 2:15am 3

OP knows this, but related thread.

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Map over vector with union eltype makes type-inference worse

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