> but I fail to see why it is a functional programming concept.
"Functional programming" means that you primarily use functions (not C functions, but mathematical pure functions) to solve your problems.
This means you won't do IO in your computation because you can't do that. It also means you won't modify data, because you can't do that either. Also you might have access to first class functions, and can pass them around as values.
If you do procedural programming in C++ but your functions don't do IO or modify (not local) values, then congrats, you're doing functional programming.
Thanks. I now see why it makes sense to me. I work in DE so in most of our cases we do streaming (IO) without any transformation (computation), and then we do transformation in a total different pipeline. We never transform anything we consumed, always keep the original copy, even if it's bad.
"Functional programming" means that you primarily use functions (not C functions, but mathematical pure functions) to solve your problems.
This means you won't do IO in your computation because you can't do that. It also means you won't modify data, because you can't do that either. Also you might have access to first class functions, and can pass them around as values.
If you do procedural programming in C++ but your functions don't do IO or modify (not local) values, then congrats, you're doing functional programming.