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   1  <?php
   2  /* Driver template for the PHP_ParserGenerator parser generator. (PHP port of LEMON)
   3  */
   4  
   5  /**
   6   * This can be used to store both the string representation of
   7   * a token, and any useful meta-data associated with the token.
   8   *
   9   * meta-data should be stored as an array
  10   */
  11  class ParseyyToken implements ArrayAccess
  12  {
  13      public $string = '';
  14      public $metadata = array();
  15  
  16      function __construct($s, $m = array())
  17      {
  18          if ($s instanceof ParseyyToken) {
  19              $this->string = $s->string;
  20              $this->metadata = $s->metadata;
  21          } else {
  22              $this->string = (string) $s;
  23              if ($m instanceof ParseyyToken) {
  24                  $this->metadata = $m->metadata;
  25              } elseif (is_array($m)) {
  26                  $this->metadata = $m;
  27              }
  28          }
  29      }
  30  
  31      function __toString()
  32      {
  33          return $this->_string;
  34      }
  35  
  36      function offsetExists($offset)
  37      {
  38          return isset($this->metadata[$offset]);
  39      }
  40  
  41      function offsetGet($offset)
  42      {
  43          return $this->metadata[$offset];
  44      }
  45  
  46      function offsetSet($offset, $value)
  47      {
  48          if ($offset === null) {
  49              if (isset($value[0])) {
  50                  $x = ($value instanceof ParseyyToken) ?
  51                      $value->metadata : $value;
  52                  $this->metadata = array_merge($this->metadata, $x);
  53                  return;
  54              }
  55              $offset = count($this->metadata);
  56          }
  57          if ($value === null) {
  58              return;
  59          }
  60          if ($value instanceof ParseyyToken) {
  61              if ($value->metadata) {
  62                  $this->metadata[$offset] = $value->metadata;
  63              }
  64          } elseif ($value) {
  65              $this->metadata[$offset] = $value;
  66          }
  67      }
  68  
  69      function offsetUnset($offset)
  70      {
  71          unset($this->metadata[$offset]);
  72      }
  73  }
  74  
  75  /** The following structure represents a single element of the
  76   * parser's stack.  Information stored includes:
  77   *
  78   *   +  The state number for the parser at this level of the stack.
  79   *
  80   *   +  The value of the token stored at this level of the stack.
  81   *      (In other words, the "major" token.)
  82   *
  83   *   +  The semantic value stored at this level of the stack.  This is
  84   *      the information used by the action routines in the grammar.
  85   *      It is sometimes called the "minor" token.
  86   */
  87  class ParseyyStackEntry
  88  {
  89      public $stateno;       /* The state-number */
  90      public $major;         /* The major token value.  This is the code
  91                       ** number for the token at this stack level */
  92      public $minor; /* The user-supplied minor token value.  This
  93                       ** is the value of the token  */
  94  };
  95  
  96  // code external to the class is included here
  97  %%
  98  
  99  // declare_class is output here
 100  %%
 101  {
 102  /* First off, code is included which follows the "include_class" declaration
 103  ** in the input file. */
 104  %%
 105  
 106  /* Next is all token values, as class constants
 107  */
 108  /* 
 109  ** These constants (all generated automatically by the parser generator)
 110  ** specify the various kinds of tokens (terminals) that the parser
 111  ** understands. 
 112  **
 113  ** Each symbol here is a terminal symbol in the grammar.
 114  */
 115  %%
 116  
 117  /* Next are that tables used to determine what action to take based on the
 118  ** current state and lookahead token.  These tables are used to implement
 119  ** functions that take a state number and lookahead value and return an
 120  ** action integer.  
 121  **
 122  ** Suppose the action integer is N.  Then the action is determined as
 123  ** follows
 124  **
 125  **   0 <= N < self::YYNSTATE                              Shift N.  That is,
 126  **                                                        push the lookahead
 127  **                                                        token onto the stack
 128  **                                                        and goto state N.
 129  **
 130  **   self::YYNSTATE <= N < self::YYNSTATE+self::YYNRULE   Reduce by rule N-YYNSTATE.
 131  **
 132  **   N == self::YYNSTATE+self::YYNRULE                    A syntax error has occurred.
 133  **
 134  **   N == self::YYNSTATE+self::YYNRULE+1                  The parser accepts its
 135  **                                                        input. (and concludes parsing)
 136  **
 137  **   N == self::YYNSTATE+self::YYNRULE+2                  No such action.  Denotes unused
 138  **                                                        slots in the yy_action[] table.
 139  **
 140  ** The action table is constructed as a single large static array $yy_action.
 141  ** Given state S and lookahead X, the action is computed as
 142  **
 143  **      self::$yy_action[self::$yy_shift_ofst[S] + X ]
 144  **
 145  ** If the index value self::$yy_shift_ofst[S]+X is out of range or if the value
 146  ** self::$yy_lookahead[self::$yy_shift_ofst[S]+X] is not equal to X or if
 147  ** self::$yy_shift_ofst[S] is equal to self::YY_SHIFT_USE_DFLT, it means that
 148  ** the action is not in the table and that self::$yy_default[S] should be used instead.  
 149  **
 150  ** The formula above is for computing the action when the lookahead is
 151  ** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
 152  ** a reduce action) then the static $yy_reduce_ofst array is used in place of
 153  ** the static $yy_shift_ofst array and self::YY_REDUCE_USE_DFLT is used in place of
 154  ** self::YY_SHIFT_USE_DFLT.
 155  **
 156  ** The following are the tables generated in this section:
 157  **
 158  **  self::$yy_action        A single table containing all actions.
 159  **  self::$yy_lookahead     A table containing the lookahead for each entry in
 160  **                          yy_action.  Used to detect hash collisions.
 161  **  self::$yy_shift_ofst    For each state, the offset into self::$yy_action for
 162  **                          shifting terminals.
 163  **  self::$yy_reduce_ofst   For each state, the offset into self::$yy_action for
 164  **                          shifting non-terminals after a reduce.
 165  **  self::$yy_default       Default action for each state.
 166  */
 167  %%
 168  /* The next thing included is series of defines which control
 169  ** various aspects of the generated parser.
 170  **    self::YYNOCODE      is a number which corresponds
 171  **                        to no legal terminal or nonterminal number.  This
 172  **                        number is used to fill in empty slots of the hash 
 173  **                        table.
 174  **    self::YYFALLBACK    If defined, this indicates that one or more tokens
 175  **                        have fall-back values which should be used if the
 176  **                        original value of the token will not parse.
 177  **    self::YYSTACKDEPTH  is the maximum depth of the parser's stack.
 178  **    self::YYNSTATE      the combined number of states.
 179  **    self::YYNRULE       the number of rules in the grammar
 180  **    self::YYERRORSYMBOL is the code number of the error symbol.  If not
 181  **                        defined, then do no error processing.
 182  */
 183  %%
 184      /** The next table maps tokens into fallback tokens.  If a construct
 185       * like the following:
 186       * 
 187       *      %fallback ID X Y Z.
 188       *
 189       * appears in the grammer, then ID becomes a fallback token for X, Y,
 190       * and Z.  Whenever one of the tokens X, Y, or Z is input to the parser
 191       * but it does not parse, the type of the token is changed to ID and
 192       * the parse is retried before an error is thrown.
 193       */
 194      static public $yyFallback = array(
 195  %%
 196      );
 197      /**
 198       * Turn parser tracing on by giving a stream to which to write the trace
 199       * and a prompt to preface each trace message.  Tracing is turned off
 200       * by making either argument NULL 
 201       *
 202       * Inputs:
 203       * 
 204       * - A stream resource to which trace output should be written.
 205       *   If NULL, then tracing is turned off.
 206       * - A prefix string written at the beginning of every
 207       *   line of trace output.  If NULL, then tracing is
 208       *   turned off.
 209       *
 210       * Outputs:
 211       * 
 212       * - None.
 213       * @param resource
 214       * @param string
 215       */
 216      static function Trace($TraceFILE, $zTracePrompt)
 217      {
 218          if (!$TraceFILE) {
 219              $zTracePrompt = 0;
 220          } elseif (!$zTracePrompt) {
 221              $TraceFILE = 0;
 222          }
 223          self::$yyTraceFILE = $TraceFILE;
 224          self::$yyTracePrompt = $zTracePrompt;
 225      }
 226  
 227      /**
 228       * Output debug information to output (php://output stream)
 229       */
 230      static function PrintTrace()
 231      {
 232          self::$yyTraceFILE = fopen('php://output', 'w');
 233          self::$yyTracePrompt = '';
 234      }
 235  
 236      /**
 237       * @var resource|0
 238       */
 239      static public $yyTraceFILE;
 240      /**
 241       * String to prepend to debug output
 242       * @var string|0
 243       */
 244      static public $yyTracePrompt;
 245      /**
 246       * @var int
 247       */
 248      public $yyidx;                    /* Index of top element in stack */
 249      /**
 250       * @var int
 251       */
 252      public $yyerrcnt;                 /* Shifts left before out of the error */
 253      /**
 254       * @var array
 255       */
 256      public $yystack = array();  /* The parser's stack */
 257  
 258      /**
 259       * For tracing shifts, the names of all terminals and nonterminals
 260       * are required.  The following table supplies these names
 261       * @var array
 262       */
 263      static public $yyTokenName = array( 
 264  %%
 265      );
 266  
 267      /**
 268       * For tracing reduce actions, the names of all rules are required.
 269       * @var array
 270       */
 271      static public $yyRuleName = array(
 272  %%
 273      );
 274  
 275      /**
 276       * This function returns the symbolic name associated with a token
 277       * value.
 278       * @param int
 279       * @return string
 280       */
 281      function tokenName($tokenType)
 282      {
 283          if ($tokenType === 0) {
 284              return 'End of Input';
 285          }
 286          if ($tokenType > 0 && $tokenType < count(self::$yyTokenName)) {
 287              return self::$yyTokenName[$tokenType];
 288          } else {
 289              return "Unknown";
 290          }
 291      }
 292  
 293      /**
 294       * The following function deletes the value associated with a
 295       * symbol.  The symbol can be either a terminal or nonterminal.
 296       * @param int the symbol code
 297       * @param mixed the symbol's value
 298       */
 299      static function yy_destructor($yymajor, $yypminor)
 300      {
 301          switch ($yymajor) {
 302          /* Here is inserted the actions which take place when a
 303          ** terminal or non-terminal is destroyed.  This can happen
 304          ** when the symbol is popped from the stack during a
 305          ** reduce or during error processing or when a parser is 
 306          ** being destroyed before it is finished parsing.
 307          **
 308          ** Note: during a reduce, the only symbols destroyed are those
 309          ** which appear on the RHS of the rule, but which are not used
 310          ** inside the C code.
 311          */
 312  %%
 313              default:  break;   /* If no destructor action specified: do nothing */
 314          }
 315      }
 316  
 317      /**
 318       * Pop the parser's stack once.
 319       *
 320       * If there is a destructor routine associated with the token which
 321       * is popped from the stack, then call it.
 322       *
 323       * Return the major token number for the symbol popped.
 324       * @param ParseyyParser
 325       * @return int
 326       */
 327      function yy_pop_parser_stack()
 328      {
 329          if (!count($this->yystack)) {
 330              return;
 331          }
 332          $yytos = array_pop($this->yystack);
 333          if (self::$yyTraceFILE && $this->yyidx >= 0) {
 334              fwrite(self::$yyTraceFILE,
 335                  self::$yyTracePrompt . 'Popping ' . self::$yyTokenName[$yytos->major] .
 336                      "\n");
 337          }
 338          $yymajor = $yytos->major;
 339          self::yy_destructor($yymajor, $yytos->minor);
 340          $this->yyidx--;
 341          return $yymajor;
 342      }
 343  
 344      /**
 345       * Deallocate and destroy a parser.  Destructors are all called for
 346       * all stack elements before shutting the parser down.
 347       */
 348      function __destruct()
 349      {
 350          while ($this->yyidx >= 0) {
 351              $this->yy_pop_parser_stack();
 352          }
 353          if (is_resource(self::$yyTraceFILE)) {
 354              fclose(self::$yyTraceFILE);
 355          }
 356      }
 357  
 358      /**
 359       * Based on the current state and parser stack, get a list of all
 360       * possible lookahead tokens
 361       * @param int
 362       * @return array
 363       */
 364      function yy_get_expected_tokens($token)
 365      {
 366          $state = $this->yystack[$this->yyidx]->stateno;
 367          $expected = self::$yyExpectedTokens[$state];
 368          if (in_array($token, self::$yyExpectedTokens[$state], true)) {
 369              return $expected;
 370          }
 371          $stack = $this->yystack;
 372          $yyidx = $this->yyidx;
 373          do {
 374              $yyact = $this->yy_find_shift_action($token);
 375              if ($yyact >= self::YYNSTATE && $yyact < self::YYNSTATE + self::YYNRULE) {
 376                  // reduce action
 377                  $done = 0;
 378                  do {
 379                      if ($done++ == 100) {
 380                          $this->yyidx = $yyidx;
 381                          $this->yystack = $stack;
 382                          // too much recursion prevents proper detection
 383                          // so give up
 384                          return array_unique($expected);
 385                      }
 386                      $yyruleno = $yyact - self::YYNSTATE;
 387                      $this->yyidx -= self::$yyRuleInfo[$yyruleno]['rhs'];
 388                      $nextstate = $this->yy_find_reduce_action(
 389                          $this->yystack[$this->yyidx]->stateno,
 390                          self::$yyRuleInfo[$yyruleno]['lhs']);
 391                      if (isset(self::$yyExpectedTokens[$nextstate])) {
 392                          $expected += self::$yyExpectedTokens[$nextstate];
 393                              if (in_array($token,
 394                                    self::$yyExpectedTokens[$nextstate], true)) {
 395                              $this->yyidx = $yyidx;
 396                              $this->yystack = $stack;
 397                              return array_unique($expected);
 398                          }
 399                      }
 400                      if ($nextstate < self::YYNSTATE) {
 401                          // we need to shift a non-terminal
 402                          $this->yyidx++;
 403                          $x = new ParseyyStackEntry;
 404                          $x->stateno = $nextstate;
 405                          $x->major = self::$yyRuleInfo[$yyruleno]['lhs'];
 406                          $this->yystack[$this->yyidx] = $x;
 407                          continue 2;
 408                      } elseif ($nextstate == self::YYNSTATE + self::YYNRULE + 1) {
 409                          $this->yyidx = $yyidx;
 410                          $this->yystack = $stack;
 411                          // the last token was just ignored, we can't accept
 412                          // by ignoring input, this is in essence ignoring a
 413                          // syntax error!
 414                          return array_unique($expected);
 415                      } elseif ($nextstate === self::YY_NO_ACTION) {
 416                          $this->yyidx = $yyidx;
 417                          $this->yystack = $stack;
 418                          // input accepted, but not shifted (I guess)
 419                          return $expected;
 420                      } else {
 421                          $yyact = $nextstate;
 422                      }
 423                  } while (true);
 424              }
 425              break;
 426          } while (true);
 427          return array_unique($expected);
 428      }
 429  
 430      /**
 431       * Based on the parser state and current parser stack, determine whether
 432       * the lookahead token is possible.
 433       * 
 434       * The parser will convert the token value to an error token if not.  This
 435       * catches some unusual edge cases where the parser would fail.
 436       * @param int
 437       * @return bool
 438       */
 439      function yy_is_expected_token($token)
 440      {
 441          if ($token === 0) {
 442              return true; // 0 is not part of this
 443          }
 444          $state = $this->yystack[$this->yyidx]->stateno;
 445          if (in_array($token, self::$yyExpectedTokens[$state], true)) {
 446              return true;
 447          }
 448          $stack = $this->yystack;
 449          $yyidx = $this->yyidx;
 450          do {
 451              $yyact = $this->yy_find_shift_action($token);
 452              if ($yyact >= self::YYNSTATE && $yyact < self::YYNSTATE + self::YYNRULE) {
 453                  // reduce action
 454                  $done = 0;
 455                  do {
 456                      if ($done++ == 100) {
 457                          $this->yyidx = $yyidx;
 458                          $this->yystack = $stack;
 459                          // too much recursion prevents proper detection
 460                          // so give up
 461                          return true;
 462                      }
 463                      $yyruleno = $yyact - self::YYNSTATE;
 464                      $this->yyidx -= self::$yyRuleInfo[$yyruleno]['rhs'];
 465                      $nextstate = $this->yy_find_reduce_action(
 466                          $this->yystack[$this->yyidx]->stateno,
 467                          self::$yyRuleInfo[$yyruleno]['lhs']);
 468                      if (isset(self::$yyExpectedTokens[$nextstate]) &&
 469                            in_array($token, self::$yyExpectedTokens[$nextstate], true)) {
 470                          $this->yyidx = $yyidx;
 471                          $this->yystack = $stack;
 472                          return true;
 473                      }
 474                      if ($nextstate < self::YYNSTATE) {
 475                          // we need to shift a non-terminal
 476                          $this->yyidx++;
 477                          $x = new ParseyyStackEntry;
 478                          $x->stateno = $nextstate;
 479                          $x->major = self::$yyRuleInfo[$yyruleno]['lhs'];
 480                          $this->yystack[$this->yyidx] = $x;
 481                          continue 2;
 482                      } elseif ($nextstate == self::YYNSTATE + self::YYNRULE + 1) {
 483                          $this->yyidx = $yyidx;
 484                          $this->yystack = $stack;
 485                          if (!$token) {
 486                              // end of input: this is valid
 487                              return true;
 488                          }
 489                          // the last token was just ignored, we can't accept
 490                          // by ignoring input, this is in essence ignoring a
 491                          // syntax error!
 492                          return false;
 493                      } elseif ($nextstate === self::YY_NO_ACTION) {
 494                          $this->yyidx = $yyidx;
 495                          $this->yystack = $stack;
 496                          // input accepted, but not shifted (I guess)
 497                          return true;
 498                      } else {
 499                          $yyact = $nextstate;
 500                      }
 501                  } while (true);
 502              }
 503              break;
 504          } while (true);
 505          return true;
 506      }
 507  
 508      /**
 509       * Find the appropriate action for a parser given the terminal
 510       * look-ahead token iLookAhead.
 511       *
 512       * If the look-ahead token is YYNOCODE, then check to see if the action is
 513       * independent of the look-ahead.  If it is, return the action, otherwise
 514       * return YY_NO_ACTION.
 515       * @param int The look-ahead token
 516       */
 517      function yy_find_shift_action($iLookAhead)
 518      {
 519          $stateno = $this->yystack[$this->yyidx]->stateno;
 520       
 521          /* if ($this->yyidx < 0) return self::YY_NO_ACTION;  */
 522          if (!isset(self::$yy_shift_ofst[$stateno])) {
 523              // no shift actions
 524              return self::$yy_default[$stateno];
 525          }
 526          $i = self::$yy_shift_ofst[$stateno];
 527          if ($i === self::YY_SHIFT_USE_DFLT) {
 528              return self::$yy_default[$stateno];
 529          }
 530          if ($iLookAhead == self::YYNOCODE) {
 531              return self::YY_NO_ACTION;
 532          }
 533          $i += $iLookAhead;
 534          if ($i < 0 || $i >= self::YY_SZ_ACTTAB ||
 535                self::$yy_lookahead[$i] != $iLookAhead) {
 536              if (count(self::$yyFallback) && $iLookAhead < count(self::$yyFallback)
 537                     && ($iFallback = self::$yyFallback[$iLookAhead]) != 0) {
 538                  if (self::$yyTraceFILE) {
 539                      fwrite(self::$yyTraceFILE, self::$yyTracePrompt . "FALLBACK " .
 540                          self::$yyTokenName[$iLookAhead] . " => " .
 541                          self::$yyTokenName[$iFallback] . "\n");
 542                  }
 543                  return $this->yy_find_shift_action($iFallback);
 544              }
 545              return self::$yy_default[$stateno];
 546          } else {
 547              return self::$yy_action[$i];
 548          }
 549      }
 550  
 551      /**
 552       * Find the appropriate action for a parser given the non-terminal
 553       * look-ahead token $iLookAhead.
 554       *
 555       * If the look-ahead token is self::YYNOCODE, then check to see if the action is
 556       * independent of the look-ahead.  If it is, return the action, otherwise
 557       * return self::YY_NO_ACTION.
 558       * @param int Current state number
 559       * @param int The look-ahead token
 560       */
 561      function yy_find_reduce_action($stateno, $iLookAhead)
 562      {
 563          /* $stateno = $this->yystack[$this->yyidx]->stateno; */
 564  
 565          if (!isset(self::$yy_reduce_ofst[$stateno])) {
 566              return self::$yy_default[$stateno];
 567          }
 568          $i = self::$yy_reduce_ofst[$stateno];
 569          if ($i == self::YY_REDUCE_USE_DFLT) {
 570              return self::$yy_default[$stateno];
 571          }
 572          if ($iLookAhead == self::YYNOCODE) {
 573              return self::YY_NO_ACTION;
 574          }
 575          $i += $iLookAhead;
 576          if ($i < 0 || $i >= self::YY_SZ_ACTTAB ||
 577                self::$yy_lookahead[$i] != $iLookAhead) {
 578              return self::$yy_default[$stateno];
 579          } else {
 580              return self::$yy_action[$i];
 581          }
 582      }
 583  
 584      /**
 585       * Perform a shift action.
 586       * @param int The new state to shift in
 587       * @param int The major token to shift in
 588       * @param mixed the minor token to shift in
 589       */
 590      function yy_shift($yyNewState, $yyMajor, $yypMinor)
 591      {
 592          $this->yyidx++;
 593          if ($this->yyidx >= self::YYSTACKDEPTH) {
 594              $this->yyidx--;
 595              if (self::$yyTraceFILE) {
 596                  fprintf(self::$yyTraceFILE, "%sStack Overflow!\n", self::$yyTracePrompt);
 597              }
 598              while ($this->yyidx >= 0) {
 599                  $this->yy_pop_parser_stack();
 600              }
 601              /* Here code is inserted which will execute if the parser
 602              ** stack ever overflows */
 603  %%
 604              return;
 605          }
 606          $yytos = new ParseyyStackEntry;
 607          $yytos->stateno = $yyNewState;
 608          $yytos->major = $yyMajor;
 609          $yytos->minor = $yypMinor;
 610          array_push($this->yystack, $yytos);
 611          if (self::$yyTraceFILE && $this->yyidx > 0) {
 612              fprintf(self::$yyTraceFILE, "%sShift %d\n", self::$yyTracePrompt,
 613                  $yyNewState);
 614              fprintf(self::$yyTraceFILE, "%sStack:", self::$yyTracePrompt);
 615              for($i = 1; $i <= $this->yyidx; $i++) {
 616                  fprintf(self::$yyTraceFILE, " %s",
 617                      self::$yyTokenName[$this->yystack[$i]->major]);
 618              }
 619              fwrite(self::$yyTraceFILE,"\n");
 620          }
 621      }
 622  
 623      /**
 624       * The following table contains information about every rule that
 625       * is used during the reduce.
 626       *
 627       * <pre>
 628       * array(
 629       *  array(
 630       *   int $lhs;         Symbol on the left-hand side of the rule
 631       *   int $nrhs;     Number of right-hand side symbols in the rule
 632       *  ),...
 633       * );
 634       * </pre>
 635       */
 636      static public $yyRuleInfo = array(
 637  %%
 638      );
 639  
 640      /**
 641       * The following table contains a mapping of reduce action to method name
 642       * that handles the reduction.
 643       * 
 644       * If a rule is not set, it has no handler.
 645       */
 646      static public $yyReduceMap = array(
 647  %%
 648      );
 649      /* Beginning here are the reduction cases.  A typical example
 650      ** follows:
 651      **  #line <lineno> <grammarfile>
 652      **   function yy_r0($yymsp){ ... }           // User supplied code
 653      **  #line <lineno> <thisfile>
 654      */
 655  %%
 656  
 657      /**
 658       * placeholder for the left hand side in a reduce operation.
 659       * 
 660       * For a parser with a rule like this:
 661       * <pre>
 662       * rule(A) ::= B. { A = 1; }
 663       * </pre>
 664       * 
 665       * The parser will translate to something like:
 666       * 
 667       * <code>
 668       * function yy_r0(){$this->_retvalue = 1;}
 669       * </code>
 670       */
 671      private $_retvalue;
 672  
 673      /**
 674       * Perform a reduce action and the shift that must immediately
 675       * follow the reduce.
 676       * 
 677       * For a rule such as:
 678       * 
 679       * <pre>
 680       * A ::= B blah C. { dosomething(); }
 681       * </pre>
 682       * 
 683       * This function will first call the action, if any, ("dosomething();" in our
 684       * example), and then it will pop three states from the stack,
 685       * one for each entry on the right-hand side of the expression
 686       * (B, blah, and C in our example rule), and then push the result of the action
 687       * back on to the stack with the resulting state reduced to (as described in the .out
 688       * file)
 689       * @param int Number of the rule by which to reduce
 690       */
 691      function yy_reduce($yyruleno)
 692      {
 693          //int $yygoto;                     /* The next state */
 694          //int $yyact;                      /* The next action */
 695          //mixed $yygotominor;        /* The LHS of the rule reduced */
 696          //ParseyyStackEntry $yymsp;            /* The top of the parser's stack */
 697          //int $yysize;                     /* Amount to pop the stack */
 698          $yymsp = $this->yystack[$this->yyidx];
 699          if (self::$yyTraceFILE && $yyruleno >= 0 
 700                && $yyruleno < count(self::$yyRuleName)) {
 701              fprintf(self::$yyTraceFILE, "%sReduce (%d) [%s].\n",
 702                  self::$yyTracePrompt, $yyruleno,
 703                  self::$yyRuleName[$yyruleno]);
 704          }
 705  
 706          $this->_retvalue = $yy_lefthand_side = null;
 707          if (array_key_exists($yyruleno, self::$yyReduceMap)) {
 708              // call the action
 709              $this->_retvalue = null;
 710              $this->{'yy_r' . self::$yyReduceMap[$yyruleno]}();
 711              $yy_lefthand_side = $this->_retvalue;
 712          }
 713          $yygoto = self::$yyRuleInfo[$yyruleno]['lhs'];
 714          $yysize = self::$yyRuleInfo[$yyruleno]['rhs'];
 715          $this->yyidx -= $yysize;
 716          for($i = $yysize; $i; $i--) {
 717              // pop all of the right-hand side parameters
 718              array_pop($this->yystack);
 719          }
 720          $yyact = $this->yy_find_reduce_action($this->yystack[$this->yyidx]->stateno, $yygoto);
 721          if ($yyact < self::YYNSTATE) {
 722              /* If we are not debugging and the reduce action popped at least
 723              ** one element off the stack, then we can push the new element back
 724              ** onto the stack here, and skip the stack overflow test in yy_shift().
 725              ** That gives a significant speed improvement. */
 726              if (!self::$yyTraceFILE && $yysize) {
 727                  $this->yyidx++;
 728                  $x = new ParseyyStackEntry;
 729                  $x->stateno = $yyact;
 730                  $x->major = $yygoto;
 731                  $x->minor = $yy_lefthand_side;
 732                  $this->yystack[$this->yyidx] = $x;
 733              } else {
 734                  $this->yy_shift($yyact, $yygoto, $yy_lefthand_side);
 735              }
 736          } elseif ($yyact == self::YYNSTATE + self::YYNRULE + 1) {
 737              $this->yy_accept();
 738          }
 739      }
 740  
 741      /**
 742       * The following code executes when the parse fails
 743       * 
 744       * Code from %parse_fail is inserted here
 745       */
 746      function yy_parse_failed()
 747      {
 748          if (self::$yyTraceFILE) {
 749              fprintf(self::$yyTraceFILE, "%sFail!\n", self::$yyTracePrompt);
 750          }
 751          while ($this->yyidx >= 0) {
 752              $this->yy_pop_parser_stack();
 753          }
 754          /* Here code is inserted which will be executed whenever the
 755          ** parser fails */
 756  %%
 757      }
 758  
 759      /**
 760       * The following code executes when a syntax error first occurs.
 761       * 
 762       * %syntax_error code is inserted here
 763       * @param int The major type of the error token
 764       * @param mixed The minor type of the error token
 765       */
 766      function yy_syntax_error($yymajor, $TOKEN)
 767      {
 768  %%
 769      }
 770  
 771      /**
 772       * The following is executed when the parser accepts
 773       * 
 774       * %parse_accept code is inserted here
 775       */
 776      function yy_accept()
 777      {
 778          if (self::$yyTraceFILE) {
 779              fprintf(self::$yyTraceFILE, "%sAccept!\n", self::$yyTracePrompt);
 780          }
 781          while ($this->yyidx >= 0) {
 782              $stack = $this->yy_pop_parser_stack();
 783          }
 784          /* Here code is inserted which will be executed whenever the
 785          ** parser accepts */
 786  %%
 787      }
 788  
 789      /**
 790       * The main parser program.
 791       * 
 792       * The first argument is the major token number.  The second is
 793       * the token value string as scanned from the input.
 794       *
 795       * @param int the token number
 796       * @param mixed the token value
 797       * @param mixed any extra arguments that should be passed to handlers
 798       */
 799      function doParse($yymajor, $yytokenvalue)
 800      {
 801  //        $yyact;            /* The parser action. */
 802  //        $yyendofinput;     /* True if we are at the end of input */
 803          $yyerrorhit = 0;   /* True if yymajor has invoked an error */
 804          
 805          /* (re)initialize the parser, if necessary */
 806          if ($this->yyidx === null || $this->yyidx < 0) {
 807              /* if ($yymajor == 0) return; // not sure why this was here... */
 808              $this->yyidx = 0;
 809              $this->yyerrcnt = -1;
 810              $x = new ParseyyStackEntry;
 811              $x->stateno = 0;
 812              $x->major = 0;
 813              $this->yystack = array();
 814              array_push($this->yystack, $x);
 815          }
 816          $yyendofinput = ($yymajor==0);
 817          
 818          if (self::$yyTraceFILE) {
 819              fprintf(self::$yyTraceFILE, "%sInput %s\n",
 820                  self::$yyTracePrompt, self::$yyTokenName[$yymajor]);
 821          }
 822          
 823          do {
 824              $yyact = $this->yy_find_shift_action($yymajor);
 825              if ($yymajor < self::YYERRORSYMBOL &&
 826                    !$this->yy_is_expected_token($yymajor)) {
 827                  // force a syntax error
 828                  $yyact = self::YY_ERROR_ACTION;
 829              }
 830              if ($yyact < self::YYNSTATE) {
 831                  $this->yy_shift($yyact, $yymajor, $yytokenvalue);
 832                  $this->yyerrcnt--;
 833                  if ($yyendofinput && $this->yyidx >= 0) {
 834                      $yymajor = 0;
 835                  } else {
 836                      $yymajor = self::YYNOCODE;
 837                  }
 838              } elseif ($yyact < self::YYNSTATE + self::YYNRULE) {
 839                  $this->yy_reduce($yyact - self::YYNSTATE);
 840              } elseif ($yyact == self::YY_ERROR_ACTION) {
 841                  if (self::$yyTraceFILE) {
 842                      fprintf(self::$yyTraceFILE, "%sSyntax Error!\n",
 843                          self::$yyTracePrompt);
 844                  }
 845                  if (self::YYERRORSYMBOL) {
 846                      /* A syntax error has occurred.
 847                      ** The response to an error depends upon whether or not the
 848                      ** grammar defines an error token "ERROR".  
 849                      **
 850                      ** This is what we do if the grammar does define ERROR:
 851                      **
 852                      **  * Call the %syntax_error function.
 853                      **
 854                      **  * Begin popping the stack until we enter a state where
 855                      **    it is legal to shift the error symbol, then shift
 856                      **    the error symbol.
 857                      **
 858                      **  * Set the error count to three.
 859                      **
 860                      **  * Begin accepting and shifting new tokens.  No new error
 861                      **    processing will occur until three tokens have been
 862                      **    shifted successfully.
 863                      **
 864                      */
 865                      if ($this->yyerrcnt < 0) {
 866                          $this->yy_syntax_error($yymajor, $yytokenvalue);
 867                      }
 868                      $yymx = $this->yystack[$this->yyidx]->major;
 869                      if ($yymx == self::YYERRORSYMBOL || $yyerrorhit ){
 870                          if (self::$yyTraceFILE) {
 871                              fprintf(self::$yyTraceFILE, "%sDiscard input token %s\n",
 872                                  self::$yyTracePrompt, self::$yyTokenName[$yymajor]);
 873                          }
 874                          $this->yy_destructor($yymajor, $yytokenvalue);
 875                          $yymajor = self::YYNOCODE;
 876                      } else {
 877                          while ($this->yyidx >= 0 &&
 878                                   $yymx != self::YYERRORSYMBOL &&
 879          ($yyact = $this->yy_find_shift_action(self::YYERRORSYMBOL)) >= self::YYNSTATE
 880                                ){
 881                              $this->yy_pop_parser_stack();
 882                          }
 883                          if ($this->yyidx < 0 || $yymajor==0) {
 884                              $this->yy_destructor($yymajor, $yytokenvalue);
 885                              $this->yy_parse_failed();
 886                              $yymajor = self::YYNOCODE;
 887                          } elseif ($yymx != self::YYERRORSYMBOL) {
 888                              $u2 = 0;
 889                              $this->yy_shift($yyact, self::YYERRORSYMBOL, $u2);
 890                          }
 891                      }
 892                      $this->yyerrcnt = 3;
 893                      $yyerrorhit = 1;
 894                  } else {
 895                      /* YYERRORSYMBOL is not defined */
 896                      /* This is what we do if the grammar does not define ERROR:
 897                      **
 898                      **  * Report an error message, and throw away the input token.
 899                      **
 900                      **  * If the input token is $, then fail the parse.
 901                      **
 902                      ** As before, subsequent error messages are suppressed until
 903                      ** three input tokens have been successfully shifted.
 904                      */
 905                      if ($this->yyerrcnt <= 0) {
 906                          $this->yy_syntax_error($yymajor, $yytokenvalue);
 907                      }
 908                      $this->yyerrcnt = 3;
 909                      $this->yy_destructor($yymajor, $yytokenvalue);
 910                      if ($yyendofinput) {
 911                          $this->yy_parse_failed();
 912                      }
 913                      $yymajor = self::YYNOCODE;
 914                  }
 915              } else {
 916                  $this->yy_accept();
 917                  $yymajor = self::YYNOCODE;
 918              }            
 919          } while ($yymajor != self::YYNOCODE && $this->yyidx >= 0);
 920      }
 921  }