Irregularity in array definition API

General Usage
1

I can define an uninitialized array this way:

a = Array{Int32, 2}(undef, 10, 10)

but I can’t define an initialized array the same way:

a = Array{Int32, 2}(42, 10, 10)

I have to use this form instead:

a = fill(Int32(42), 10, 10)

Is there a deeper reason for this? The first form is also used to initialize arrays with ‘nothing’ or ‘missing’, so it overlaps initialized and uninitialized construction category.

2

What value should the array be initialized with when you do Array{Int32, 2}(42, 10, 10)? Do you want the first value to be used to fill the array? Or should 42 be interpreted as a dimension of the resulting array?

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3

Array{Int,2}(undef, N1, N2) is like Array{Int,2}(undef, (N1,N2)).
Array{Int,2}(42, N1, N2) could be like Array{Int,2}(42, (N1,N2)) which could be as fill(42, (N1,N2)).

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4

Array constructors in general are in need of some love.

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5

I see the problem with this option now. As @JeffreySarnoff noted, Array{Int32, 2}(42, (10, 10)) could be the way out.

EDIT

BTW, fill(42, 10, 10) doesn’t make it obvious which arguments are dimensions and which is the value to fill with.

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