180 lines
5.7 KiB
PHP
180 lines
5.7 KiB
PHP
<?php
|
|
/**
|
|
* PHP_ParserGenerator, a php 5 parser generator.
|
|
*
|
|
* This is a direct port of the Lemon parser generator, found at
|
|
* {@link http://www.hwaci.com/sw/lemon/}
|
|
*
|
|
* PHP version 5
|
|
*
|
|
* LICENSE: This source file is subject to version 3.01 of the PHP license
|
|
* that is available through the world-wide-web at the following URI:
|
|
* http://www.php.net/license/3_01.txt. If you did not receive a copy of
|
|
* the PHP License and are unable to obtain it through the web, please
|
|
* send a note to license@php.net so we can mail you a copy immediately.
|
|
*
|
|
* @category php
|
|
* @package PHP_ParserGenerator
|
|
* @author Gregory Beaver <cellog@php.net>
|
|
* @copyright 2006 Gregory Beaver
|
|
* @license http://www.php.net/license/3_01.txt PHP License 3.01
|
|
* @version CVS: $Id$
|
|
* @since File available since Release 0.1.0
|
|
*/
|
|
/**
|
|
* Every shift or reduce operation is stored as one of the following objects.
|
|
*
|
|
* @package PHP_ParserGenerator
|
|
* @author Gregory Beaver <cellog@php.net>
|
|
* @copyright 2006 Gregory Beaver
|
|
* @license http://www.php.net/license/3_01.txt PHP License 3.01
|
|
* @version 0.1.0
|
|
* @since Class available since Release 0.1.0
|
|
*/
|
|
class PHP_ParserGenerator_Action {
|
|
const SHIFT = 1,
|
|
ACCEPT = 2,
|
|
REDUCE = 3,
|
|
ERROR = 4,
|
|
/**
|
|
* Was a reduce, but part of a conflict
|
|
*/
|
|
CONFLICT = 5,
|
|
/**
|
|
* Was a shift. Precedence resolved conflict
|
|
*/
|
|
SH_RESOLVED = 6,
|
|
/**
|
|
* Was a reduce. Precedence resolved conflict
|
|
*/
|
|
RD_RESOLVED = 7,
|
|
/**
|
|
* Deleted by compression
|
|
* @see PHP_ParserGenerator::CompressTables()
|
|
*/
|
|
NOT_USED = 8;
|
|
/**
|
|
* The look-ahead symbol that triggers this action
|
|
* @var PHP_ParserGenerator_Symbol
|
|
*/
|
|
public $sp; /* The look-ahead symbol */
|
|
/**
|
|
* This defines the kind of action, and must be one
|
|
* of the class constants.
|
|
*
|
|
* - {@link PHP_ParserGenerator_Action::SHIFT}
|
|
* - {@link PHP_ParserGenerator_Action::ACCEPT}
|
|
* - {@link PHP_ParserGenerator_Action::REDUCE}
|
|
* - {@link PHP_ParserGenerator_Action::ERROR}
|
|
* - {@link PHP_ParserGenerator_Action::CONFLICT}
|
|
* - {@link PHP_ParserGenerator_Action::SH_RESOLVED}
|
|
* - {@link PHP_ParserGenerator_Action:: RD_RESOLVED}
|
|
* - {@link PHP_ParserGenerator_Action::NOT_USED}
|
|
*/
|
|
public $type;
|
|
/**
|
|
* The new state, if this is a shift,
|
|
* the parser rule index, if this is a reduce.
|
|
*
|
|
* @var PHP_ParserGenerator_State|PHP_ParserGenerator_Rule
|
|
*/
|
|
public $x;
|
|
/**
|
|
* The next action for this state.
|
|
* @var PHP_ParserGenerator_Action
|
|
*/
|
|
public $next;
|
|
|
|
/**
|
|
* Compare two actions
|
|
*
|
|
* This is used by {@link Action_sort()} to compare actions
|
|
*/
|
|
static function actioncmp(PHP_ParserGenerator_Action $ap1,
|
|
PHP_ParserGenerator_Action $ap2)
|
|
{
|
|
$rc = $ap1->sp->index - $ap2->sp->index;
|
|
if ($rc === 0) {
|
|
$rc = $ap1->type - $ap2->type;
|
|
}
|
|
if ($rc === 0) {
|
|
if ($ap1->type != self::REDUCE &&
|
|
$ap1->type != self::RD_RESOLVED &&
|
|
$ap1->type != self::CONFLICT) {
|
|
throw new Exception('action has not been processed: ' .
|
|
$ap1->sp->name);
|
|
}
|
|
if ($ap2->type != self::REDUCE &&
|
|
$ap2->type != self::RD_RESOLVED &&
|
|
$ap2->type != self::CONFLICT) {
|
|
throw new Exception('action has not been processed: ' .
|
|
$ap2->sp->name);
|
|
}
|
|
$rc = $ap1->x->index - $ap2->x->index;
|
|
}
|
|
return $rc;
|
|
}
|
|
|
|
/**
|
|
* create linked list of PHP_ParserGenerator_Actions
|
|
*
|
|
* @param PHP_ParserGenerator_Action|null
|
|
* @param int one of the class constants from PHP_ParserGenerator_Action
|
|
* @param PHP_ParserGenerator_Symbol
|
|
* @param PHP_ParserGenerator_Symbol|PHP_ParserGenerator_Rule
|
|
*/
|
|
static function Action_add(&$app, $type, PHP_ParserGenerator_Symbol $sp, $arg)
|
|
{
|
|
$new = new PHP_ParserGenerator_Action;
|
|
$new->next = $app;
|
|
$app = $new;
|
|
$new->type = $type;
|
|
$new->sp = $sp;
|
|
$new->x = $arg;
|
|
}
|
|
|
|
/**
|
|
* Sort parser actions
|
|
* @see PHP_ParserGenerator_Data::FindActions()
|
|
*/
|
|
static function Action_sort(PHP_ParserGenerator_Action $ap)
|
|
{
|
|
$ap = PHP_ParserGenerator::msort($ap, 'next', array('PHP_ParserGenerator_Action', 'actioncmp'));
|
|
return $ap;
|
|
}
|
|
|
|
/**
|
|
* Print an action to the given file descriptor. Return FALSE if
|
|
* nothing was actually printed.
|
|
* @see PHP_ParserGenerator_Data::ReportOutput()
|
|
*/
|
|
function PrintAction($fp, $indent)
|
|
{
|
|
$result = 1;
|
|
switch ($this->type)
|
|
{
|
|
case self::SHIFT:
|
|
fprintf($fp, "%${indent}s shift %d", $this->sp->name, $this->x->statenum);
|
|
break;
|
|
case self::REDUCE:
|
|
fprintf($fp, "%${indent}s reduce %d", $this->sp->name, $this->x->index);
|
|
break;
|
|
case self::ACCEPT:
|
|
fprintf($fp, "%${indent}s accept", $this->sp->name);
|
|
break;
|
|
case self::ERROR:
|
|
fprintf($fp, "%${indent}s error", $this->sp->name);
|
|
break;
|
|
case self::CONFLICT:
|
|
fprintf($fp, "%${indent}s reduce %-3d ** Parsing conflict **", $this->sp->name, $this->x->index);
|
|
break;
|
|
case self::SH_RESOLVED:
|
|
case self::RD_RESOLVED:
|
|
case self::NOT_USED:
|
|
$result = 0;
|
|
break;
|
|
}
|
|
return $result;
|
|
}
|
|
}
|
|
?>
|