//C style varaible actions for a Recursice Descent Parser CvarExample.c
//written 3/10/08 by George Hamer

/*********************************************************************
Implements production rule DECL
DECL -> TYPE IDLIST | 
		empty_production
**********************************************************************/
void DECL()
{
		VarType TypVal;

        if(token==intt||token==floatt||token==chart){
                TYPE(TypVal); //synthesizes the type
                IDLIST(TypVal); //now inherit the type
        }
		else
                return; //empty_production
}
/*********************************************************************
Implements production rule TYPE
TYPE -> int|float|char
**********************************************************************/
void TYPE(VarTyp &TypVar)
{
        TypVar=token; //Assume we have a correct type, if not we will
		              //catch it with the following if statement!
        if(token==intt)
                Match(intt);
        else if(token==floatt)
                Match(floatt);
        else if(token==chart)
                Match(chart);
        else MatchError(14,token);  //Expected: float, int, or char
}

/*********************************************************************
Implements production rule IDLIST
IDLIST -> idt IDTAIL;DECL
**********************************************************************/
void IDLIST(VarTyp TypVal)
{
        EntryPtr ptr;

        ptr=LookUp(lexeme);
        if(ptr && ptr->depth==depth){
                cout<<"Error duplicate id- line"<<LineNum<<endl;
                exit(1);
        }
        Insert(lexeme,token,depth);
        ptr=LookUp(lexeme);
        SetType(ptr,TypVal);
        Match(idt);
        IDTAIL(TypVal); //IDTAIL must inherit the type
        Match(semicolont);
        DECL();
}
/*********************************************************************
Implements production rule IDTAIL
IDTAIL -> , idt IDTAIL | empty_production
**********************************************************************/
void IDTAIL(VarTyp TypVal)
{
        EntryPtr ptr;
        if(token==commat){
                Match(commat);
                ptr=LookUp(lexeme);
                if(ptr && ptr->depth==depth){
                        cout<<"Error duplicate id- line"<<LineNum<<endl;
                        exit(0);
                }
                Insert(lexeme,token,depth);
                ptr=LookUp(lexeme);
                SetType(ptr,TypVal);
                Match(idt);
                IDTAIL();
        }
        else
                return; //empty_production
}

/**************************************************************************
 Set the symbol table entry type to varEntry and now set the variable to the 
 inherited attribute TypVal
 **************************************************************************/
void SetType(EntryPtr ptr, VarTyp TypVal)
{
    ptr->TypeOfEntry=varEntry; //because of the union
    ptr->var.TypeOfVariable = TypVal;;
}