Functional Programming, Programming, Programming Languages.
you haven’t done Python, this is how a λ expression in Python looks like, filter(lambda x: x % 3 == 0, [1, 2, 3, 4, 5, 6, 7, 8, 9]) Anyway I didn’t bother to read a lot into all those and just carried on with the code. I am a big fan of Paul Graham’s essays. After reading this one(you should too)