module AST where


data Program t = Program [FunDef t]
  deriving (Show)

data FunDef t = FunDef Name (Maybe Type) [FunEq t]
  deriving (Show)

newtype Name = Name String
  deriving (Show)

data Type
    = TApp Name [Type]
    | TTup [Type]
    | TList Type
    | TFun Type Type
  deriving (Show)

data FunEq t = FunEq Name [Pattern t] (RHS t)
  deriving (Show)

data Pattern t
    = PWildcard t
    | PVar t Name
    | PAs t Name (Pattern t)
    | PCon t Name [Pattern t]
    | PList t [Pattern t]
    | PTup t [Pattern t]
  deriving (Show)

data RHS t
    = Guarded [(Expr t, Expr t)]
    | Plain (Expr t)
  deriving (Show)

data Expr t
    = ELit t Literal
    | EList t [Expr t]
    | ETup t [Expr t]
    | EApp t (Expr t) (Expr t)
    | EOp t (Expr t) Operator (Expr t)
    | EIf t (Expr t) (Expr t) (Expr t)
    | ECase t (Expr t) [(Pattern t, RHS t)]
    | ELet t [FunDef t] (Expr t)
  deriving (Show)

data Literal = LInt Int | LFloat Double | LChar Char | LString String
  deriving (Show)

data Operator = OAdd | OSub | OMul | ODiv | OMod
  deriving (Show)