Question

I defined my own method to access elements as:

class Array2
  def [](key)
    if key.kind_of?(Integer)
      @elements[key]
    else
      # ...
    end
  end
end

If I had previously declared @elements as Array.new, both the operations:

list = Array2.new
# ...
puts list[0]
puts list.[](0)

work properly. Why is the first operation acceptable?

Answer 1

Both the list[0] and list.[](0) syntaxes mean the exact same thing. They call the [] method with an argument 0 on the list object.