Is there collection of very simple, well written, commented implementations of machine learning algorithms?

I want to learn more about machine learning, but, considering how big the field is, instead of buying a pile of long books and diving into oceans of words, I'd really prefer something more akin to browsing some well written code in a simple programming language (Python, Scheme, Haskell, JavaScript...), with comments explaining what it does and why it works, and play with that code. That would be such a productive learning experience. Is there anything like that? A git repo?