MODULE {TigerAS} {} {}

imports
{
import TigerTypes
import UU.Scanner.Position
}

DATA Program | Program expr:Expr
  
DATA DeclGroup 
   | VarDec   pos:Pos 
              ident:VarIdent 
              tp:{Maybe TypeIdent} 
              expr:Expr

   | TypeDecs decs:TypeDecs

   | FunDecs  decs:FunDecs
   
DATA TypeDec  
   | TypeDec pos:Pos 
             ident:TypeIdent 
             tp:Type 

DATA FunDec   
   | FunDec pos:Pos
            ident:VarIdent 
   	    argTps:{[TypedVar]} 
	    retTp:{Maybe TypeIdent} 
	    body:Expr

TYPE TypeDecs = [TypeDec] 
TYPE FunDecs  = [FunDec ] 

TYPE AssignFields = [AssignField] 
TYPE Declarations = [DeclGroup]

TYPE Args  = [Expr]

DATA LValue 
   | Sub   pos:Pos
           expr:LValue 
           index:Expr
           

   | Dot   pos:Pos 
           expr:LValue 
           ident:VarIdent

   | Ident ident:VarIdent

DATA Expr
   | LValue     lvalue:LValue

   | Apply      ident:VarIdent 
                args:Args

   | RecordVal  ident:TypeIdent 
                fields:AssignFields

   | ArrayVal   ident:TypeIdent 
                size:Expr 
                init:Expr

   | IntLit     value:Integer 
                pos:Pos

   | StringLit  value:String 
                pos:Pos 

   | While      pos:Pos 
                cond:Expr 
                body:Expr

   | For        pos:Pos 
                ident:VarIdent 
                low:Expr 
                hi:Expr 
                body:Expr

   | If         pos:Pos 
                cond:Expr 
                thenPart:Expr 
                elsePart:Expr

   | Let        pos:Pos 
                decls:Declarations
                body:Expr

   | Assign     lvalue:LValue
                pos:Pos 
                expr:Expr

   | Op         op:String 
                pos:Pos 
                left:Expr 
                right:Expr

   | UnOp       pos:Pos 
                op:String 
                expr:Expr

   | Skip

   | Nil        pos:Pos

   | Break      pos:Pos

   | Sequence   left:Expr 
                right:Expr

DATA AssignField 
   | AssignField ident:VarIdent expr:Expr