definition module AST

from Data.Maybe import :: Maybe
from StdOverloaded import class toString, class ==, class zero, class <

:: Pos = {line :: Int, col :: Int}
:: AST = AST [FunDecl]
:: VarDecl = VarDecl Pos (Maybe Type) String Expr
:: TVar :== String
:: Type 
	= TupleType (Type, Type)
	| ListType Type
	| IdType TVar 
	| IntType 
	| BoolType
	| CharType
    | VoidType
	| FuncType Type
    | (->>) infixl 7 Type Type
:: Expr 
	= VarExpr Pos VarDef
	| Op2Expr Pos Expr Op2 Expr
	| Op1Expr Pos Op1 Expr
	| IntExpr Pos Int
	| CharExpr Pos Char
	| BoolExpr Pos Bool
	| FunExpr Pos String [Expr] [FieldSelector]
	| EmptyListExpr Pos 
	| TupleExpr Pos (Expr, Expr)
    | LambdaExpr Pos [String] Expr
:: VarDef = VarDef String [FieldSelector]
:: FieldSelector = FieldHd | FieldTl | FieldFst | FieldSnd
:: Op1 = UnNegation | UnMinus
:: Op2 = BiPlus | BiMinus | BiTimes | BiDivide | BiMod | BiEquals | BiLesser |
	BiGreater | BiLesserEq | BiGreaterEq | BiUnEqual | BiAnd | BiOr | BiCons
:: FunDecl = FunDecl Pos String [String] (Maybe Type) [VarDecl] [Stmt]
:: Stmt 
	= IfStmt Expr [Stmt] [Stmt]
	| WhileStmt Expr [Stmt]
	| AssStmt VarDef Expr
	| FunStmt String [Expr] [FieldSelector]
	| ReturnStmt (Maybe Expr)

instance toString Pos
instance toString Type
instance toString AST
instance toString FieldSelector
instance toString Op2
instance toString Expr
instance toString VarDecl
instance toString FunDecl

instance zero Pos
instance == Op1
instance == Op2
instance < Op1
instance < Op2
instance == Type