Left funktionen og HTML tags

Kode 

function &close_html(&$a_text){
    $s=array();//The Stack; 
    $t=strpos($a_text,"<",$t);
    $l=strlen($a_text);
    while($t!==false){
        $t=strpos($a_text,"<",$t);
        if($t===false){
            break;
        }else{
            if($t+1==$l){
                $a_text[$t]="";
                break;            
            }
            if(preg_match('/[a-zA-Z]/',$a_text[$t+1])==1){
                $tag="";
                $t++;
                while($t<$l&&$a_text[$t]!=" "&&$a_text[$t]!=">"){
                    $tag.=$a_text[$t];
                    $t++;
                }
                if($t==$l){
                    $a_text=substr_replace($a_text,"",-strlen($tag)-1,strlen($tag)+1);
                    break;
                }
                $p=strpos($a_text,">",$t);
                if($p===false){
                    $from=$t-strlen($tag)-2;
                    $a_text=substr_replace($a_text,"",$from,$l-$from);
                    break;
                }elseif($a_text[$p-1]!="/"){
                    array_push($s,$tag);
                }
                $t=$p+1;
                continue;
            }
            if($a_text[$t+1]=="/"){
                $p=strpos($a_text,">",$t+1);
                if($p===false){
                    $a_text=substr_replace($a_text,"",$t,$l-$t);
                    break;
                }else{
                    $t=$p+1;
                    array_pop($s);
                    continue;
                }
            }
        }
    }
    if(count($s)>0){
        for($i=count($s)-1;$i>-1;$i--){
            $a_text.="</".$s[$i].">";
        }
    }
    return $a_text;
}