Hi all. I have a function in which I create an array but the type of the array is

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1

Hi all. I have a function in which I create an array but the type of the array is selected by the user meaning that it is passed as an argument something like:

function f(T)
    arr = Matrix{T}(undef,3,3)
    return arr
end

What is a correct type-stable way to do this? This is basically the function to load a bunch of data into named tuples with prespecified (I cannot use DataFrames).

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2

Solution from Slack by Valentin:

probably

julia> function f(::Type{T}) where T    
           return Matrix{T}(undef, 3, 3)
       end

you have to remember that the type of Float64 is DataType (like almost all types), so the compiler doesn’t know which type it is. typing ::Type{T} allows the compiler to know which type exactly it is

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