<?php
/* Driver template for the PHP_ParserGenerator parser generator. (PHP port of LEMON)
*/
/**
* This can be used to store both the string representation of
* a token, and any useful meta-data associated with the token.
*
* meta-data should be stored as an array
*/
class ParseyyToken implements ArrayAccess
{
public $string = '';
public $metadata = array();
function __construct($s, $m = array())
{
if ($s instanceof ParseyyToken) {
$this->string = $s->string;
$this->metadata = $s->metadata;
} else {
$this->string = (string) $s;
if ($m instanceof ParseyyToken) {
$this->metadata = $m->metadata;
$this->metadata = $m;
}
}
}
function __toString()
{
return $this->_string;
}
function offsetExists($offset)
{
return isset($this->metadata[$offset]);
}
function offsetGet($offset)
{
return $this->metadata[$offset];
}
function offsetSet($offset, $value)
{
if ($offset === null) {
if (isset($value[0])) {
$x = ($value instanceof ParseyyToken) ?
$value->metadata : $value;
return;
}
$offset =
count($this->metadata); }
if ($value === null) {
return;
}
if ($value instanceof ParseyyToken) {
if ($value->metadata) {
$this->metadata[$offset] = $value->metadata;
}
} elseif ($value) {
$this->metadata[$offset] = $value;
}
}
function offsetUnset($offset)
{
unset($this->metadata[$offset]);
}
}
/** The following structure represents a single element of the
* parser's stack. Information stored includes:
*
* + The state number for the parser at this level of the stack.
*
* + The value of the token stored at this level of the stack.
* (In other words, the "major" token.)
*
* + The semantic value stored at this level of the stack. This is
* the information used by the action routines in the grammar.
* It is sometimes called the "minor" token.
*/
class ParseyyStackEntry
{
public $stateno; /* The state-number */
public $major; /* The major token value. This is the code
** number for the token at this stack level */
public $minor; /* The user-supplied minor token value. This
** is the value of the token */
};
// code external to the class is included here
%%
// declare_class is output here
%%
{
/* First off, code is included which follows the "include_class" declaration
** in the input file. */
%%
/* Next is all token values, as class constants
*/
/*
** These constants (all generated automatically by the parser generator)
** specify the various kinds of tokens (terminals) that the parser
** understands.
**
** Each symbol here is a terminal symbol in the grammar.
*/
%%
/* Next are that tables used to determine what action to take based on the
** current state and lookahead token. These tables are used to implement
** functions that take a state number and lookahead value and return an
** action integer.
**
** Suppose the action integer is N. Then the action is determined as
** follows
**
** 0 <= N < self::YYNSTATE Shift N. That is,
** push the lookahead
** token onto the stack
** and goto state N.
**
** self::YYNSTATE <= N < self::YYNSTATE+self::YYNRULE Reduce by rule N-YYNSTATE.
**
** N == self::YYNSTATE+self::YYNRULE A syntax error has occurred.
**
** N == self::YYNSTATE+self::YYNRULE+1 The parser accepts its
** input. (and concludes parsing)
**
** N == self::YYNSTATE+self::YYNRULE+2 No such action. Denotes unused
** slots in the yy_action[] table.
**
** The action table is constructed as a single large static array $yy_action.
** Given state S and lookahead X, the action is computed as
**
** self::$yy_action[self::$yy_shift_ofst[S] + X ]
**
** If the index value self::$yy_shift_ofst[S]+X is out of range or if the value
** self::$yy_lookahead[self::$yy_shift_ofst[S]+X] is not equal to X or if
** self::$yy_shift_ofst[S] is equal to self::YY_SHIFT_USE_DFLT, it means that
** the action is not in the table and that self::$yy_default[S] should be used instead.
**
** The formula above is for computing the action when the lookahead is
** a terminal symbol. If the lookahead is a non-terminal (as occurs after
** a reduce action) then the static $yy_reduce_ofst array is used in place of
** the static $yy_shift_ofst array and self::YY_REDUCE_USE_DFLT is used in place of
** self::YY_SHIFT_USE_DFLT.
**
** The following are the tables generated in this section:
**
** self::$yy_action A single table containing all actions.
** self::$yy_lookahead A table containing the lookahead for each entry in
** yy_action. Used to detect hash collisions.
** self::$yy_shift_ofst For each state, the offset into self::$yy_action for
** shifting terminals.
** self::$yy_reduce_ofst For each state, the offset into self::$yy_action for
** shifting non-terminals after a reduce.
** self::$yy_default Default action for each state.
*/
%%
/* The next thing included is series of defines which control
** various aspects of the generated parser.
** self::YYNOCODE is a number which corresponds
** to no legal terminal or nonterminal number. This
** number is used to fill in empty slots of the hash
** table.
** self::YYFALLBACK If defined, this indicates that one or more tokens
** have fall-back values which should be used if the
** original value of the token will not parse.
** self::YYSTACKDEPTH is the maximum depth of the parser's stack.
** self::YYNSTATE the combined number of states.
** self::YYNRULE the number of rules in the grammar
** self::YYERRORSYMBOL is the code number of the error symbol. If not
** defined, then do no error processing.
*/
%%
/** The next table maps tokens into fallback tokens. If a construct
* like the following:
*
* %fallback ID X Y Z.
*
* appears in the grammer, then ID becomes a fallback token for X, Y,
* and Z. Whenever one of the tokens X, Y, or Z is input to the parser
* but it does not parse, the type of the token is changed to ID and
* the parse is retried before an error is thrown.
*/
static public $yyFallback = array(
%%
);
/**
* Turn parser tracing on by giving a stream to which to write the trace
* and a prompt to preface each trace message. Tracing is turned off
* by making either argument NULL
*
* Inputs:
*
* - A stream resource to which trace output should be written.
* If NULL, then tracing is turned off.
* - A prefix string written at the beginning of every
* line of trace output. If NULL, then tracing is
* turned off.
*
* Outputs:
*
* - None.
* @param resource
* @param string
*/
static function Trace($TraceFILE, $zTracePrompt)
{
if (!$TraceFILE) {
$zTracePrompt = 0;
} elseif (!$zTracePrompt) {
$TraceFILE = 0;
}
self::$yyTraceFILE = $TraceFILE;
self::$yyTracePrompt = $zTracePrompt;
}
/**
* Output debug information to output (php://output stream)
*/
static function PrintTrace()
{
self::$yyTraceFILE = fopen('php://output', 'w');
self::$yyTracePrompt = '';
}
/**
* @var resource|0
*/
static public $yyTraceFILE;
/**
* String to prepend to debug output
* @var string|0
*/
static public $yyTracePrompt;
/**
* @var int
*/
public $yyidx; /* Index of top element in stack */
/**
* @var int
*/
public $yyerrcnt; /* Shifts left before out of the error */
/**
* @var array
*/
public $yystack = array(); /* The parser's stack */
/**
* For tracing shifts, the names of all terminals and nonterminals
* are required. The following table supplies these names
* @var array
*/
static public $yyTokenName = array(
%%
);
/**
* For tracing reduce actions, the names of all rules are required.
* @var array
*/
static public $yyRuleName = array(
%%
);
/**
* This function returns the symbolic name associated with a token
* value.
* @param int
* @return string
*/
function tokenName($tokenType)
{
if ($tokenType === 0) {
return 'End of Input';
}
if ($tokenType >
0 &&
$tokenType <
count(self::$yyTokenName)) { return self::$yyTokenName[$tokenType];
} else {
return "Unknown";
}
}
/**
* The following function deletes the value associated with a
* symbol. The symbol can be either a terminal or nonterminal.
* @param int the symbol code
* @param mixed the symbol's value
*/
static function yy_destructor($yymajor, $yypminor)
{
switch ($yymajor) {
/* Here is inserted the actions which take place when a
** terminal or non-terminal is destroyed. This can happen
** when the symbol is popped from the stack during a
** reduce or during error processing or when a parser is
** being destroyed before it is finished parsing.
**
** Note: during a reduce, the only symbols destroyed are those
** which appear on the RHS of the rule, but which are not used
** inside the C code.
*/
%%
default: break; /* If no destructor action specified: do nothing */
}
}
/**
* Pop the parser's stack once.
*
* If there is a destructor routine associated with the token which
* is popped from the stack, then call it.
*
* Return the major token number for the symbol popped.
* @param ParseyyParser
* @return int
*/
function yy_pop_parser_stack()
{
if (!count($this->yystack)) { return;
}
if (self::$yyTraceFILE && $this->yyidx >= 0) {
self::$yyTracePrompt . 'Popping ' . self::$yyTokenName[$yytos->major] .
"\n");
}
$yymajor = $yytos->major;
self::yy_destructor($yymajor, $yytos->minor);
$this->yyidx--;
return $yymajor;
}
/**
* Deallocate and destroy a parser. Destructors are all called for
* all stack elements before shutting the parser down.
*/
function __destruct()
{
while ($this->yyidx >= 0) {
$this->yy_pop_parser_stack();
}
fclose(self::$yyTraceFILE);
}
}
/**
* Based on the current state and parser stack, get a list of all
* possible lookahead tokens
* @param int
* @return array
*/
function yy_get_expected_tokens($token)
{
$state = $this->yystack[$this->yyidx]->stateno;
$expected = self::$yyExpectedTokens[$state];
if (in_array($token, self::$yyExpectedTokens[$state], true)) {
return $expected;
}
$stack = $this->yystack;
$yyidx = $this->yyidx;
do {
$yyact = $this->yy_find_shift_action($token);
if ($yyact >= self::YYNSTATE && $yyact < self::YYNSTATE + self::YYNRULE) {
// reduce action
$done = 0;
do {
if ($done++ == 100) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
// too much recursion prevents proper detection
// so give up
}
$yyruleno = $yyact - self::YYNSTATE;
$this->yyidx -= self::$yyRuleInfo[$yyruleno]['rhs'];
$nextstate = $this->yy_find_reduce_action(
$this->yystack[$this->yyidx]->stateno,
self::$yyRuleInfo[$yyruleno]['lhs']);
if (isset(self::$yyExpectedTokens[$nextstate])) {
$expected += self::$yyExpectedTokens[$nextstate];
if (in_array($token,
self::$yyExpectedTokens[$nextstate], true)) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
}
}
if ($nextstate < self::YYNSTATE) {
// we need to shift a non-terminal
$this->yyidx++;
$x = new ParseyyStackEntry;
$x->stateno = $nextstate;
$x->major = self::$yyRuleInfo[$yyruleno]['lhs'];
$this->yystack[$this->yyidx] = $x;
continue 2;
} elseif ($nextstate == self::YYNSTATE + self::YYNRULE + 1) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
// the last token was just ignored, we can't accept
// by ignoring input, this is in essence ignoring a
// syntax error!
} elseif ($nextstate === self::YY_NO_ACTION) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
// input accepted, but not shifted (I guess)
return $expected;
} else {
$yyact = $nextstate;
}
} while (true);
}
break;
} while (true);
}
/**
* Based on the parser state and current parser stack, determine whether
* the lookahead token is possible.
*
* The parser will convert the token value to an error token if not. This
* catches some unusual edge cases where the parser would fail.
* @param int
* @return bool
*/
function yy_is_expected_token($token)
{
if ($token === 0) {
return true; // 0 is not part of this
}
$state = $this->yystack[$this->yyidx]->stateno;
if (in_array($token, self::$yyExpectedTokens[$state], true)) { return true;
}
$stack = $this->yystack;
$yyidx = $this->yyidx;
do {
$yyact = $this->yy_find_shift_action($token);
if ($yyact >= self::YYNSTATE && $yyact < self::YYNSTATE + self::YYNRULE) {
// reduce action
$done = 0;
do {
if ($done++ == 100) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
// too much recursion prevents proper detection
// so give up
return true;
}
$yyruleno = $yyact - self::YYNSTATE;
$this->yyidx -= self::$yyRuleInfo[$yyruleno]['rhs'];
$nextstate = $this->yy_find_reduce_action(
$this->yystack[$this->yyidx]->stateno,
self::$yyRuleInfo[$yyruleno]['lhs']);
if (isset(self::$yyExpectedTokens[$nextstate]) &&
in_array($token, self::$yyExpectedTokens[$nextstate], true)) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
return true;
}
if ($nextstate < self::YYNSTATE) {
// we need to shift a non-terminal
$this->yyidx++;
$x = new ParseyyStackEntry;
$x->stateno = $nextstate;
$x->major = self::$yyRuleInfo[$yyruleno]['lhs'];
$this->yystack[$this->yyidx] = $x;
continue 2;
} elseif ($nextstate == self::YYNSTATE + self::YYNRULE + 1) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
if (!$token) {
// end of input: this is valid
return true;
}
// the last token was just ignored, we can't accept
// by ignoring input, this is in essence ignoring a
// syntax error!
return false;
} elseif ($nextstate === self::YY_NO_ACTION) {
$this->yyidx = $yyidx;
$this->yystack = $stack;
// input accepted, but not shifted (I guess)
return true;
} else {
$yyact = $nextstate;
}
} while (true);
}
break;
} while (true);
return true;
}
/**
* Find the appropriate action for a parser given the terminal
* look-ahead token iLookAhead.
*
* If the look-ahead token is YYNOCODE, then check to see if the action is
* independent of the look-ahead. If it is, return the action, otherwise
* return YY_NO_ACTION.
* @param int The look-ahead token
*/
function yy_find_shift_action($iLookAhead)
{
$stateno = $this->yystack[$this->yyidx]->stateno;
/* if ($this->yyidx < 0) return self::YY_NO_ACTION; */
if (!isset(self::$yy_shift_ofst[$stateno])) {
// no shift actions
return self::$yy_default[$stateno];
}
$i = self::$yy_shift_ofst[$stateno];
if ($i === self::YY_SHIFT_USE_DFLT) {
return self::$yy_default[$stateno];
}
if ($iLookAhead == self::YYNOCODE) {
return self::YY_NO_ACTION;
}
$i += $iLookAhead;
if ($i < 0 || $i >= self::YY_SZ_ACTTAB ||
self::$yy_lookahead[$i] != $iLookAhead) {
if (count(self::$yyFallback) && $iLookAhead < count(self::$yyFallback)
&& ($iFallback = self::$yyFallback[$iLookAhead]) != 0) {
if (self::$yyTraceFILE) {
fwrite(self::$yyTraceFILE, self::$yyTracePrompt . "FALLBACK " .
self::$yyTokenName[$iLookAhead] . " => " .
self::$yyTokenName[$iFallback] . "\n");
}
return $this->yy_find_shift_action($iFallback);
}
return self::$yy_default[$stateno];
} else {
return self::$yy_action[$i];
}
}
/**
* Find the appropriate action for a parser given the non-terminal
* look-ahead token $iLookAhead.
*
* If the look-ahead token is self::YYNOCODE, then check to see if the action is
* independent of the look-ahead. If it is, return the action, otherwise
* return self::YY_NO_ACTION.
* @param int Current state number
* @param int The look-ahead token
*/
function yy_find_reduce_action($stateno, $iLookAhead)
{
/* $stateno = $this->yystack[$this->yyidx]->stateno; */
if (!isset(self::$yy_reduce_ofst[$stateno])) {
return self::$yy_default[$stateno];
}
$i = self::$yy_reduce_ofst[$stateno];
&n
