It always amazes me when die-hard FP'ers get it all wrong and think OOP is at war with their beloved FP. Well no, plenty of OOP languages exist that combine FP and OO together. Scala.. C#.. Clojure.. etc.
Most functional programming languages don't do immutability by default (which anyways, is an aspect of the library that can choose to be or not to be; LINQ definitely is). There are also no true scotts men.
Considering there is no (AFAIK) agreed upon definition of what an FP language is, I'm using classical as "common and found in older FP languages", not saying that an FP language which isn't immutable per default is not FP.
I'm think of Haskell, OCaml or (AFAIK) Erlang. From what I read, Clojure has also a lot of emphasis on immutability.
Haskell and OCaml aren't really that old. I'm thinking ML and Lisp, scheme, which don't focus on immutability.
Both clojure and haskell have mutability, just at differing granularities (haskell monads, clojure replace the world object). They can do it with referential transparency though (which is probably your meaning, obviously pure immutability is impossible and not sensical).
Haskell is from 1990 and OCaml from 1996, it's not awfully recent.
> Both clojure and haskell have mutability, just at differing granularities (haskell monads, clojure replace the world object). They can do it with referential transparency though (which is probably your meaning, obviously pure immutability is impossible and not sensical).
Well, you have to have to be able to manipulate state somehow (even if, at least on the surface, the state monad emulates mutability, as opposed to, eg, OCaml's notion of mutation, which is very explicit in what it does). But the point is that it is not the path of least resistance in these languages.
They are not very old either, at least not compared to Lisp (60s), scheme and the MLs (70s/80s). Haskell is quite brand spanking new in comparison to the old guard.
What C# lacks for me in FP, case matching, has little to do with purity. The FP story involves purity but is not dominated by it. List comprehensions still work in C# even though you can theoretically side effect in your select and filter functions.
Did you just illustrate his point? No one in the comments mentioned OOP and you were the one to bring it up to disparage it. He was just responding to your hypocrisy.
