"lisp it is up to the developer whether or not a function will be referentially transparent" Although that may compromise the ability of the compiler to detect

"lisp it is up to the developer whether or not a function will be referentially transparent" Although that may compromise the ability of the compiler to detect mistakes even when the developer writes all referentially-transparent functions. Not sure about that, but I suspect that it does in practice (currently) even if not theoretically inherent.