Accessing sets of particular indexes over multiple dimensions

General Usage
1

How can you use maps or other techniques to instantly access every nth element of every mth element of every kth element of every element of multidimensional array? Is that allowed?

# array def
a = Array{Vector{Vector{SparseVector}}}(a, b)
2

A minimal working example would be nice, but something like

function nested(A, k, m, n)
    _acc(i) = B -> B[i]
    map(_acc(n) ∘_acc(m) ∘ _acc(k), A)
end

should work, if I parsed the “… of …” nesting right.

3 
function kmnofa(a)
    el=[]
    for i in eachindex(a)
         push!(el, a[i][k][m][n])
    end
    return el
end