Non-numerical use cases for functional programming?

Question

I just finished reading a book on scala. What strikes me is that every single example in the whole book was numerical in some form or another.

Like a lot of programm

Answer 1

The more I use a functional style, the better I like it. Consider this Python fragment from another question:

>>> testlist
[1, 2, 3, 5, 3, 1, 2, 1, 6]
>>> [i for i,x in enumerate(testlist) if x == 1]
[0, 5, 7]

This is admittedly a more or less mathematical statement, but there are lots of generators in Python. Once you get used to it, using a list comprehension in place of a loop is both easy to understand, and less likely to have a bug (you don't get "off by one" bugs.)