[jwdunne]

I'm no expert but due to the language I think you need to specify types somewhere. It just offloads it to your test code as opposed to the algorithms.

With python, your algorithm will work with the primitives without specifying either in the algorithm or test code. You only need to specify type, i.e maybe a new class and definitely instantiation, if you want to use something more abstract.

This would be true of Ruby and other dynamically typed languages. For beginner algorithms courses at least, a dynamically typed languages makes more sense since the algorithms taught are only clouded by typing. Complexity theory still applies and what not.

Maybe if learning algorithms that do heavy crunching, a lower level language, probably with static types, may be used but by that point you're not going to mind type info.