Do we have something similar to undef for non-arrays? Wishful thinking: f() = a::Tuple{Int, Int} where T = 5, undef

Could you explain what you want that to do?

I’m trying to implement node allocators, which could make use of undefined memory like arrays do.

You could use a Ref, e.g. Ref{Tuple{Int, Int}}() will be a mutable container that can be updated later. Or you could use StaticArrays.jl’s MVector. e.g. MVector{2, Int}(undef).

Ref{Tuple{Int, Int}}() I understand, but if we have a vector of these there a probably some allocations required.

If you have a vector of them then you just use undef. julia> v = Vector{Tuple{Int, Int}}(undef, 2) 2-element Vector{Tuple{Int64, Int64}}: (9, 4) (11, 5)

Undef for non-arrays

General Usage

goerch October 10, 2021, 3:15pm 7

Just noticed Create a struct with uninitialized fields - #5 by dfdx in the feed.

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Undef for non-arrays

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