ParserFunc.y

 
%{

	#include "ParseTree.h" 
	#include <stdio.h>
	#include <string.h>
	#include <stdlib.h>
	#include <iostream>

	extern "C" int yyfunclex();
	extern "C" int yyfuncparse();
	extern "C" void yyfuncerror(char *s);
  
	// this is the final parse tree that is returned	
	struct FuncOperator *finalfunc;	

%}

// this stores all of the types returned by production rules
%union {
 	struct FuncOperand *myOperand;
	struct FuncOperator *myOperator; 
	char *actualChars;
	char whichOne;
}

%token <actualChars> Name
%token <actualChars> Float
%token <actualChars> Int

%type <myOperand> SimpleExp
%type <myOperator> CompoundExp
%type <whichOne> Op 

%start CompoundExp


//******************************************************************************
// SECTION 3
//******************************************************************************
/* This is the PRODUCTION RULES section which defines how to "understand" the 
 * input language and what action to take for each "statment"
 */

%%

CompoundExp: SimpleExp Op CompoundExp
{
	$$ = (struct FuncOperator *) malloc (sizeof (struct FuncOperator));	
	$$->leftOperator = (struct FuncOperator *) malloc (sizeof (struct FuncOperator));
	$$->leftOperator->leftOperator = NULL;
	$$->leftOperator->leftOperand = $1;
	$$->leftOperator->right = NULL;
	$$->leftOperand = NULL;
	$$->right = $3;
	$$->code = $2;	

	finalfunc = $$;
}

| '(' CompoundExp ')' Op CompoundExp
{
	$$ = (struct FuncOperator *) malloc (sizeof (struct FuncOperator));	
	$$->leftOperator = $2;
	$$->leftOperand = NULL;
	$$->right = $5;
	$$->code = $4;	

	finalfunc = $$;
}

| '(' CompoundExp ')'
{
	$$ = $2;

	finalfunc = $$;
}

| SimpleExp
{
	$$ = (struct FuncOperator *) malloc (sizeof (struct FuncOperator));	
	$$->leftOperator = NULL;
	$$->leftOperand = $1;
	$$->right = NULL;	

	finalfunc = $$;
}

| '-' CompoundExp
{
	$$ = (struct FuncOperator *) malloc (sizeof (struct FuncOperator));	
	$$->leftOperator = $2;
	$$->leftOperand = NULL;
	$$->right = NULL;	
	$$->code = '-';

	finalfunc = $$;
}
;

Op: '-'
{
	$$ = '-';
}

| '+'
{
	$$ = '+';
}

| '*'
{
	$$ = '*';
}

| '/'
{
	$$ = '/';
}
;


SimpleExp: 

Float
{
        // construct and send up the operand containing the FP number
        $$ = (struct FuncOperand *) malloc (sizeof (struct FuncOperand));
        $$->code = DOUBLE;
        $$->value = $1;
} 

| Int
{
        // construct and send up the operand containing the integer
        $$ = (struct FuncOperand *) malloc (sizeof (struct FuncOperand));
        $$->code = INT;
        $$->value = $1;
} 

| Name
{
        // construct and send up the operand containing the name
        $$ = (struct FuncOperand *) malloc (sizeof (struct FuncOperand));
        $$->code = NAME;
        $$->value = $1;
}
;

%%