Bison parser doesn't recognize the "New" keyword [closed] - c++

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I am trying to build a simple compiler and I am in the stage to test the Bison parser I created recently over some sample .decaf files, the parser works well with all keywords and the grammar's terminal and non-terminal tokens/types and rest of the grammar rules and actions, but there is only one problem that my parser does not recognize the New keyword/operator, when ever a statement includes a New keyword it results into an error in the output!
Defining New as a terminal token
%token T_New
CFG grammar rule and action for Expr that also includes rule and action for T_New
Expr : LValue '=' Expr { $$=new AssignExpr($1,new Operator(#2,"="),$3); }
| '(' Expr ')' { $$=$2; }
| Expr '+' Expr { $$=new ArithmeticExpr($1,new Operator(#2,"+"),$3); }
| Expr '-' Expr { $$=new ArithmeticExpr($1,new Operator(#2,"-"),$3); }
| Expr '*' Expr { $$=new ArithmeticExpr($1,new Operator(#2,"*"),$3); }
| Expr '/' Expr { $$=new ArithmeticExpr($1,new Operator(#2,"/"),$3); }
| Expr '%' Expr { $$=new ArithmeticExpr($1,new Operator(#2,"%"),$3); }
| '-' Expr %prec T_UnaryMinus { $$=new ArithmeticExpr(new Operator(#1,"-"),$2); }
| Expr T_And Expr { $$=new LogicalExpr($1,new Operator(#2,"&&"),$3); }
| Expr T_Or Expr { $$=new LogicalExpr($1,new Operator(#2,"||"),$3); }
| Expr '<' Expr { $$=new RelationalExpr($1,new Operator(#2,"<"),$3); }
| Expr T_LessEqual Expr { $$=new RelationalExpr($1,new Operator(#2,"<="),$3); }
| Expr '>' Expr { $$=new RelationalExpr($1,new Operator(#2,">"),$3); }
| Expr T_GreaterEqual Expr { $$=new RelationalExpr($1,new Operator(#2,">="),$3); }
| Expr T_Equal Expr { $$=new EqualityExpr($1,new Operator(#2,"=="),$3); }
| Expr T_NotEqual Expr { $$=new EqualityExpr($1,new Operator(#2,"!="),$3); }
| '!' Expr { $$=new LogicalExpr(new Operator(#1, "!"), $2); }
| T_ReadInteger '(' ')' { $$=new ReadIntegerExpr(#1); }
| T_ReadLine '(' ')' { $$=new ReadLineExpr(#1); }
| T_New Identifier { $$=new NewExpr(#2,new NamedType($2)); }
| T_NewArray '(' Expr ',' Type ')' { $$=new NewArrayExpr(#1,$3,$5); }
| LValue { $$=$1; }
| T_This { $$=new This(#1); }
| Call { $$=$1; }
| Constant { $$=$1; }
;
for example I have this sample file interface.decaf for testing and it has a main function as below:
void main() {
Colorable s;
Color green;
green = New(Color);
green.SetRGB(0, 0, 255);
s = New(Rectangle);
s.SetColor(green);
}
But when I run my parser over this sample file in the terminal I get this error:
*** Error line 33.
green = New(Color);
*** syntax error
I tried with other sample files and noticed that any file that has a statement that mentions 'New' keyword returns the same error.
I got some hint from this question that probably New keyword is mixed up between C and C++ and that's why its not recognized by bison. but I am still not able to figure out how to fix this ! Can anyone help please ?

Answer 1

Your grammar has a rule
| T_New Identifier { ...
matching a New keyword followed immediately by an identifier. However, your examples all have parenthesis around the identifier:
green = New(Color)
s = new(Rectangle)
thus the syntax error you are seeing -- the input has a ( where the grammar expects an identifier...