The C language is purely functional
There has been a scurry of reaction on twitter and reddit to Robert Fischer’s post saying that Scala is Not a Functional Programming Language. James Iry responded by saying that analogous reasoning leads to the conclusion that Erlang is Not Functional
My first inclination was to suggest that Haskell, as commonly practiced (with monadic IO), is not a functional language either. Instead, I’m going to explain how it is that the C language is purely functional.