本帖最后由 xuzuning 于 2012-08-27 16:40:33 编辑
最近尝试做了文法分析的东东，问题较多。
请提建议。代码放不下，分两页。下载地址 http://download.csdn.net/detail/xuzuning/4529066
include 'ttrie.php';<br>
<br>
class Rule extends TTrie {<br>
public $rule = array();<br>
public $savematch = 0;<br>
<br>
function __construct($s='') {<br>
$this->set( array(<br>
' ' => 'Separated',<br>
"\r\n" => 'set_rule',<br>
"\n" => 'set_rule',<br>
"\t" => 'Separated',<br>
'->' => 'Separated',<br>
'→' => 'Separated',<br>
'|' => 'set_parallel_rule',<br>
));<br>
$this->match($s);<br>
if($this->rule[0][0] == $this->rule[0][1]) {<br>
if(count($this->rule[0]) == 2) $this->rule[0][0] .= "'";<br>
else array_unshift($this->rule, array($this->rule[0][0]."'", $this->rule[0][0]));<br>
}else {<br>
$c = $this->rule[0][0];<br>
$n = 0;<br>
foreach($this->rule as $r) if($r[0] == $c) $n++;<br>
if($n > 1) array_unshift($this->rule, array($this->rule[0][0]."'", $this->rule[0][0]));<br>
}<br>
}<br>
function Separated() {<br>
}<br>
function set_rule() {<br>
$this->rule[] = $this->buffer;<br>
$this->buffer = array();<br>
}<br>
function set_parallel_rule() {<br>
$t = $this->buffer[0];<br>
$this->set_rule();<br>
$this->buffer[] = $t;<br>
}<br>
}<br>
<br>
<br>
class Grammar {<br>
var $closure = array();<br>
var $first = array();<br>
var $follow = array();<br>
var $rule = array();<br>
var $identifier = array();<br>
var $leay = array();<br>
var $forecast = array();<br>
var $stack = array();<br>
var $ll = 'LL(0)';<br>
var $lr = 'LR(0)';<br>
<br>
function __construct($s='') {<br>
$p = new Rule($s);<br>
$this->rule = $p->rule;<br>
$this->set_grammar();<br>
}<br>
<br>
function set_grammar() {<br>
foreach($this->rule as $rule) {<br>
if(! in_array($rule[0], $this->identifier)) $this->identifier[] = $rule[0];<br>
}<br>
foreach($this->rule as $rule) {<br>
foreach($rule as $v)<br>
if(! in_array($v, $this->identifier) && ! in_array($v, $this->leay))<br>
$this->leay[] = $v;<br>
}<br>
$this->set_first();<br>
$this->set_follow();<br>
$this->set_closure();<br>
$this->set_select();<br>
$this->set_forecast();<br>
}<br>
function set_first() {<br>
foreach($this->rule as $rule) $this->first[$rule[0]] = array();<br>
//直接收取 形如U->a…的产生式（其中a是终结符），把a收入到First(U)中<br>
foreach($this->rule as $v) {<br>
if(in_array($v[1], $this->leay)) $this->first[$v[0]][] = $v[1];<br>
}<br>
//反复传递 形入U->P1P2P3…Pn的产生式（其中P是非终结符），应先把First(P1)中的全部内容传送到First(U)中,如果P1中有ε，把First(P2)中的内容传送到First(U)中,类推直到Pi中无ε<br>
do {<br>
$t = serialize($this->first);<br>
foreach($this->rule as $rule) {<br>
for($i=1; $i<count class="clear">
</count>
