I accept that this is a widely used phrase now but I never understood why just using map/filter/reduce and avoiding state is enough for code to be called "functional programming".
Most functional languages feature pattern matching, algebraic data types, purity, currying, strong typing, type inference, recursion instead of loops and types that cannot be null. It's a completely different style of coding. Adding map/filter/reduce to an imperative language doesn't get you close to the level of robustness and ease of implementation for that safety you'd get in a functional language.
Most functional languages feature pattern matching, algebraic data types, purity, currying, strong typing, type inference, recursion instead of loops and types that cannot be null. It's a completely different style of coding. Adding map/filter/reduce to an imperative language doesn't get you close to the level of robustness and ease of implementation for that safety you'd get in a functional language.