How can I access multiple values of a dictionary using a tuple of keys?

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How can I access multiple values of a dictionary using a tuple of keys?

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I found this other post, but it doesn’t seem to work in Julia 1.5

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By @pfitzseb:

I’d just broadcast getindex :

julia> d = Dict(:a => 1, :b => 2, :c => 3)
Dict{Symbol,Int64} with 3 entries:
:a => 1
:b => 2
:c => 3julia> getindex.(Ref(d), (:a, :b, :c))
(1, 2, 3)

The Ref(...) does the trick.

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Do you know what the Ref is necessary?

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The Ref is necessary for the Dict to be treated as an scalar by the broadcast instead of a collection. Wrapping in an unitary tuple would have the same effect: getindex.((d,), (:a, :b, :c)).

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I have found the following to benchmark slightly faster than the Ref method:

tuple((d[i] for i in (:a, :b, :c))...)

This has the added bonus of also not needing the tuple or splatting (...) if you are only iterating through results anyway (or replacing tuple with another function). With the tuple and the splatting, this will produce the same result as the Ref method.