SBSPSS/Utils/Scripter/parser.y

%{
/****************************************************************************
parser.y
ParserWizard generated YACC file.

Date: 07 December 2000
****************************************************************************/

#include "lexer.h"
#include "codegen.h"


%}

/////////////////////////////////////////////////////////////////////////////
// declarations section

// parser name
%name myparser

// class definition
{
	// place any extra class members here
}

// constructor
{
	// place any extra initialisation code here
}

//// attribute type
//%include {
//#ifndef YYSTYPE
//#define YYSTYPE int
//#endif
//}

%union {
	int				variableIdx;
	signed short	value;
	class CTreeNode	*treenode;
}



// place any declarations here

%token	STOP
%token	IF
%token	ELSE
%token	PAUSE
%token	PRINT
%token	ASSIGN
%token	EQUAL
%token	NOTEQUAL
%token	PLUS
%token	END_STMT
%token	OPEN_PAR
%token	CLOSE_PAR
%token	BEGIN_CS
%token	END_CS
%token	<variableIdx>	VARIABLE
%token	<value>			VALUE

%type	<treenode>		program statement_list statement
%type	<treenode>		assign_expression
%type	<treenode>		expression equal_expression notequal_expression
%type	<treenode>		variable
%type	<treenode>		value

%%


/////////////////////////////////////////////////////////////////////////////
// rules section

// place your YACC rules here (there must be at least one)

program
	:statement_list										{s_baseTreeNode=$1;}
	;													
														
statement_list											
	:statement_list statement							{$$=new CTreeNode(STMT_LIST,$1,$2);}
	|													{$$=new CTreeNode(EMPTY_STMT);}
	;

statement
	:END_STMT											{$$=new CTreeNode(EMPTY_STMT);}
	|STOP END_STMT										{$$=new CTreeNode(STOP_STMT);}
	|PAUSE END_STMT										{$$=new CTreeNode(PAUSE_STMT);}
	|PRINT OPEN_PAR value CLOSE_PAR END_STMT			{$$=new CTreeNode(PRINT_STMT,$3);}
	|assign_expression END_STMT							{$$=$1;}
	|IF OPEN_PAR expression CLOSE_PAR statement			{$$=new CTreeNode(IF_STMT,$3,$5);}
	|IF OPEN_PAR expression CLOSE_PAR statement ELSE statement	{$$=new CTreeNode(IFELSE_STMT,$3,$5,$7);}
	|BEGIN_CS statement_list END_CS						{$$=new CTreeNode(STMT_LIST,$2);}
	;


assign_expression
	:variable ASSIGN value								{$$=new CTreeNode(ASSIGN_EXPR,$1,$3);}
	;													
														
														
expression												
	:OPEN_PAR expression CLOSE_PAR						{$$=$2;}
	|equal_expression									{$$=$1;}
	|notequal_expression								{$$=$1;}
	;													
														
equal_expression										
	:value EQUAL value									{$$=new CTreeNode(EQUAL_EXPR,$1,$3);}
	;													
														
notequal_expression										
	:value NOTEQUAL value								{$$=new CTreeNode(NOTEQUAL_EXPR,$1,$3);}
	;													
														
														
variable												
	:VARIABLE											{$$=new CTreeNode(VARIABLE_EXPR,$1);}		// variable id
	;													
														
value													
	:VALUE												{$$=new CTreeNode(VALUE_EXPR,$1);}
	|VARIABLE											{$$=new CTreeNode(VARIABLE_EXPR,$1);}		// variable value
	|value PLUS value									{$$=new CTreeNode(PLUS_EXPR,$1,$3);}
	;													

%%


/////////////////////////////////////////////////////////////////////////////
// programs section

int main(void)
{
	int n=1;

openOutputFile("test.dat");
	mylexer lexer;
	myparser parser;
	if(parser.yycreate(&lexer))
	{
		if(lexer.yycreate(&parser))
		{
			n=parser.yyparse();
		}
	}

if(s_baseTreeNode)
{
	s_baseTreeNode->generateCode(true);
}
closeOutputFile();

	return n;
}