The manual section on Parametric Types says that Julia’s type parameters are invariant but the section on Tuple Types says Tuple types are covariant in their parameters I’m just curious about the reason behind this design choice. It seems a bit confusing to me as a Julia novice, but I’m s…

Why are tuples covariant?

Oscar_Smith August 15, 2020, 6:07pm 2

The reason here is mainly historical. There actually is a proposal to change it for Julia 2.0 https://github.com/JuliaLang/julia/issues/24614

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