-- My lispy!!!!!

import Data.HashMap.Strict

type Variable = String

type Environment = HashMap

type Operand
  = Lambda [Variable] RetType Operand
  | Operation
  | Variable Variable
  | Integer Int

type Operator
  = Add Operand Operand
--  | Sub Operand Operand
--  | Mul Operand Operand

type Oporation = Operator Operand Operand

eval :: Operand -> Operand
eval (Integer i) = i
eval (Variable v) = lookup env v
eval (Operation op o1 o2) = eval

eval :: Operation -> Operand
eval Add o1 o2 = eval o1 + eval o2
-- eval Sub o1 o2 e = eval o1 - eval o2
-- eval Mul o1 o2 e = eval o1 * eval o2
-- eval Div o1 o1 e = eval o1 / eval o2