Fatal error: Call to undefined function get_header() in

display_errors = off
error_reporting=E_ALL&~E_NOTICE

diff --git a/lib/YAML/Dumper.pm b/lib/YAML/Dumper.pm
index d7a7981..ec47341 100644
--- a/lib/YAML/Dumper.pm
+++ b/lib/YAML/Dumper.pm
@@ -2,16 +2,16 @@ use v6;
 class YAML::Dumper;
 has $.out = [];
-has $.seen is rw = {};
+has $.seen = {};
 has $.tags = {};
 has $.anchors = {};
 has $.level is rw = 0;
-has $.id is rw = 1;
+has $.id = 1;
 has $.info = [];
 method dump($object) {
     $.prewalk($object);
-    $.seen = {};
+    $!seen = {};
     $.dump_document($object);
     return $.out.join('');
 }
@@ -45,11 +45,11 @@ method dump_collection($node, $kind, $function) {
 method check_special($node) {
     my $first = 1;
-    if $.anchors.exists($node.WHICH) {
-    if $.anchors.exists($node.WHICH) {
+    if $.anchors{$node.WHICH}:exists {
         push $.out, ' ', '&' ~ $.anchors{$node.WHICH};
         $first = 0;
     }
-    if $.tags.exists($node.WHICH) {
+    if $.tags{$node.WHICH}:exists {
         push $.out, ' ', '!' ~ $.tags{$node.WHICH};
         $first = 0;
     }
@@ -64,7 +64,7 @@ method indent($first) {
             return;
         }
         if $.info[*-1]<kind> eq 'seq' && $.info[*-2]<kind> eq 'map' {
-            $seq_in_map = 1;
+            $seq_in_map = 0;
         }
     }
     push $.out, "n";
@@ -155,7 +155,8 @@ method dump_object($node, $type) {
     $.tags{$repr.WHICH} = $type;
     for $node.^attributes -> $a {
         my $name = $a.name.substr(2);
-        my $value = pir::getattribute__PPs($node, $a.name);     #RAKUDO
+        #my $value = pir::getattribute__PPs($node, $a.name);     #RAKUDO
+        my $value = $a.get_value($node);                         #for non-parrot
         $repr{$name} = $value;
     }
     $.dump_node($repr);
这里的 $.seen 和 $!seen 是不是晕掉了？其实 $.seen 就相当于先声明了 $!seen 后再自动创建一个 method seen() { return $!seen }。

<?php
$rest = substr ("abcdef", 1); // returns "bcdef"
$rest = substr ("abcdef", 1, 3); // returns "bcd"
?>

<?php
$rest = substr ("abcdef", -1); // returns "f"
$rest = substr ("abcdef", -2); // returns "ef"
$rest = substr ("abcdef", -3, 1); // returns "d"
?>

<?php
$rest = substr ("abcdef", 1, -1); // returns "bcde"
?>

<?php
$rest = substr ("中国人", 1, -1); // returns "fdsafsda" 就是乱码了
?>

<?php
    echo mb_substr("php中文字符encode",0,4,"utf-8");
?>

function sub_str($str, $length = 0, $append = true)
{
    $str = trim($str);
    $strlength = strlen($str);
 
    if ($length == 0 || $length >= $strlength)
    {
        return $str;  //截取长度等于0或大于等于本字符串的长度，返回字符串本身
    }
    elseif ($length < 0)  //如果截取长度为负数
    {
        $length = $strlength + $length;//那么截取长度就等于字符串长度减去截取长度
        if ($length < 0)
        {
            $length = $strlength;//如果截取长度的绝对值大于字符串本身长度，则截取长度取字符串本身的长度
        }
    }
 
    if (function_exists('mb_substr'))
    {
        $newstr = mb_substr($str, 0, $length, EC_CHARSET);
    }
    elseif (function_exists('iconv_substr'))
    {
        $newstr = iconv_substr($str, 0, $length, EC_CHARSET);
    }
    else
    {
        //$newstr = trim_right(substr($str, 0, $length));
        $newstr = substr($str, 0, $length);
    }
 
    if ($append && $str != $newstr)
    {
        $newstr .= '...';
    }
 
    return $newstr;
}

function download($file_url,$new_name=''){
 if(!isset($file_url)||trim($file_url)==''){
  return '500';
 }
 if(!file_exists($file_url)){//检查文件是否存在
  return '404';
 }
 $file_name=basename($file_url);
 $file_type=explode('.',$file_url);
 $file_type=$file_type[count($file_type)-1];
 $file_name=trim($new_name=='')?$file_name:urlencode($new_name).'.'.$file_type;
 //输入文件标签phpernote
 header("Content-type: application/octet-stream");
 header("Accept-Ranges: bytes");
 header("Accept-Length: ".filesize($file_url));
 header("Content-Disposition: attachment; filename=".$file_name);
 //输出文件内容
 @readfile($file_type);
}