How to make a struct support subsetting elements 'recursively'

New to Julia
1

Suppose I have the following:

struct mystuff
  x::Array{Float64,1}
  y::Array{Float64,1}
  mystuff(n) = begin
    s = new(Array{Float64,1}(undef,n),Array{Float64,1}(undef,n))
    return s
  end
  mystuff(x,y) = begin
    s = new(x,y)
    return s
  end
end

check = mystuff([1,2,3],[8,9,10])

How do I make this support subsetting like check2=check[<indexes>] so that the following happens:

julia> check2=check[1:2]
julia> check2.x
2-element Array{Float64,1}:
 1.0
 2.0
julia> check2.y
2-element Array{Float64,1}:
 9.0
 10.0
2

As one solution, you could override Base.getindex:

julia> import Base: getindex

julia> getindex(s::mystuff, i) = mystuff(s.x[i], s.y[i])
getindex (generic function with 545 methods)

julia> check = mystuff([1,2,3],[8,9,10])
mystuff([1.0, 2.0, 3.0], [8.0, 9.0, 10.0])

julia> check[1:2]
mystuff([1.0, 2.0], [8.0, 9.0])

This is a typical Julia pattern. Use the type system to create specific behavior and override Base or other functions (i.e. add new methods of those functions) locally to support your types.

3

perfect, thanks