~verifypn-cpn/verifypn/colored

%{

#include <stdio.h>

#include "PQL.h"

#include "Expressions.h"

using namespace PetriEngine::PQL;

 

AssignmentExpression* assignment;

extern int pqlalex();

void pqlaerror(const char *s) {printf("ERROR: %s\n", s);}

%}

 

%name-prefix "pqla"

%expect 2

 

/* Possible data representation */

%union {

        PetriEngine::PQL::Expr* expr;

        PetriEngine::PQL::AssignmentExpression* assExpr;

        std::string *string;

        int token;

}

 

/* Terminal type definition */

%token <string> ID INT

%token <token> LPAREN RPAREN ASSIGN SEMI

%token <token> AND OR NOT

%token <token> EQUAL NEQUAL LESS LESSEQUAL GREATER GREATEREQUAL

%token <token> PLUS MINUS MULTIPLY

 

/* Nonterminal type definition */

%type <expr> expr term factor

%type <assExpr> assignment

 

/* Operator precedence, more possibly coming */

 

%start root

 

%%

 

root    : assignment                    { assignment = (AssignmentExpression*)$1; }

                | error                                 { assignment = NULL; yyerrok; }

                ;

 

assignment      : ID ASSIGN expr SEMI assignment        { ((AssignmentExpression*)$5)->prepend(*$1, $3); delete $1;

                                                                                                  $$ = ((AssignmentExpression*)$5)}

                        | ID ASSIGN expr SEMI                           { AssignmentExpression* a = new AssignmentExpression();

                                                                                                  a->prepend(*$1, $3); delete $1;

                                                                                                  $$ = a;}

                        | ID ASSIGN expr                                        { AssignmentExpression* a = new AssignmentExpression();

                                                                                                  a->prepend(*$1, $3); delete $1;

                                                                                                  $$ = a;}

                        ;

 

expr    : expr PLUS term        { $$ = new PlusExpr($1, $3); }

                | expr MINUS term       { $$ = new SubtractExpr($1, $3); }

                | MINUS expr            { $$ = new MinusExpr($2); }

                | term                          { $$ = $1; }

                ;

 

term    : term MULTIPLY factor  { $$ = new MultiplyExpr($1, $3); }

                | factor                                { $$ = $1; }

                ;

 

factor  : LPAREN expr RPAREN    { $$ = $2; }

                | INT                   { $$ = new LiteralExpr(atol($1->c_str())); delete $1; }

                | ID                    { $$ = new IdentifierExpr(*$1, @1.first_column); delete $1; }

                ;