struct Foo val::Vector{Int} end How can I check if a type is recursively immutable? I tried function recursively_immutable(type) !type.mutable && all(recursively_immutable(ft) for ft in fieldtypes(type)) end but it doesn’t work on vectors, because vectors don’t have any fieldtypes.

Check recursive immutability

jzr June 12, 2021, 9:35pm 3

I think StaticArrays can have mutable interiors.

sa = SVector{3}([[],[2],[3]])
push!(sa[1], 1)

Same with FunctionalCollections.PersistentVector.

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