a=Vector{Union{Missing, Int64}}() push!(a,1) push!(a,missing) push! to the union vector.Can this cause type instability?

No. Julia implements Union by storing a separate variable which tells which type the value has. The code then has branches, but no general type instability. You can check code stability yourself by using macro @code_warntype like @code_warntype f([1,2,3]).

Does union cause type instability？

General Usage

jd-foster December 3, 2022, 11:53am 2

Type stabilty is generally a property of functions, not collections.

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Does union cause type instability？

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