Let's Implement the Map Method from First Principles

After writing the above post, I got a few emails asking me to explain how anonymous functions are different from regular functions and when to use them.In short, you know they are an important concept, and all the examples make sense, but you've no idea when you might use them in real-world.I banged my head against a brick wall trying to figure out how higher-order functions work for a long time, and there didn't seem to be any concise, clear explanation on just how does it work. So here's my attempt at explaining them with a very simple example.Let's try to implement the ubiquitous and omnipresent map method in Ruby, from the first principles.