example from https://tarquin-the-brave.github.io/blog/posts/re-learning-haskell-2/

prog5.hs

data Prog a = Running a | AwaitInput a | End a | Crashed String deriving(Show, Eq)

data Intcode = Intcode {
  input::[Int],
  code::[Int],
  -- ip: Instruction Pointer
  ip::Int,
  -- rb: Relative Base
  rb::Int,
  output::[Int]
} deriving(Show, Eq)