You give a list of things you'd have to teach before you can explain how the #each works, but are you sure you really need to teach how #each works to explain w

You give a list of things you'd have to teach before you can explain how the #each works, but are you sure you really need to teach how #each works to explain what it does? I think I would rather teach that #each is a method that iterates over the elements of the array calling the code block for every element. This only requires you to teach variables, arrays, the if statement, goto/jumps and objects with their methods. And frankly it being ruby, I don't think it's bad at all to teach objects and their methods, before teaching iterations. Maybe it's not in line with your hard way philosophy, but explaining for loops with goto/jumps seems a bit abstract to me. Don't you need to explain how instructions are mapped to memory addresses and the instruction register to really do so? An each method can be explained with a simple recursive function, no need to dive into hocus pocus CPU details.