1: Cleaner and more concise. Perhaps safer, as the less code there is going to performing a task, the fewer places I can make a mistake. More importantly, it directs me to think about my problem from a higher level of abstraction.

2: I do mix both paradigms, so I’m not stuck without imperative features. That being said, there are times where I feel like my attempts to move a concept into FP forces me to make some less than ideal choices to fit it into the paradigm. If those are in inner loops, I forgo functional programming to do precisely what I need. (For example, managing exceptional cases or heterogeneous actions can be awkward.)

3: I would have used them more. I’ve always been a fan of comprehensions and map c/o Python, but my code would have been more efficient and concise had I started earlier. The additions of cppitertools, range-v3, <algorithm> and <functional> make functional programming both easy and efficient in C++ in ways it was not prior to C++1[147]. I think Python made fp accessible by putting it in an imperative language which is concise and readable.