Question

我试图从数据结构中打印出一个YAML文档，特别是一个哈希数组，这就是我认为YAML :: dump返回的内容。这是我用来构建YAML文档并将其序列化的Perl代码。

my @tagobj_header_table =
{
core => {
    type => $tagobj_type,
    size => $tagobj_size,
    blob => $tagobj_blob,
},
text => {
     lines => {
     {
         offset => 0,
         length => 1
     },
     {
         offset => 1,
         length => 5,
     },
     {
         offset => 6,
         length => 7,
     },
     {
         offset => 13,
         length => 13,
     },
     {
         offset => 26,
         length => 1,
     }
     }
  }
};

my $dumper = YAML::Dumper->new;
my $tagobj_contents = $dumper->dump(@tagobj_header_table);
print $tagobj_contents;

这是我希望YAML文档看起来像什么，有一些Perl字符串替换。

---
core:
    type: $tagobj_type
    size: $tagobj_size
    blob: $tagobj_blob
text:
    lines:
        - offset: 0
          length: 1
        - offset: 1
          length: 5
        - offset: 6
          length: 7
        - offset: 13
          length: 13
        - offset: 26
          length: 1

以下是控制台的输出。

---
core:
    blob: build\content\objects\36d80951814b5f08c7ba34cd7a5459b4c212ee6200ce247ac2a13d24b2fc0d57
    size: 31
    type: blob/text
text:
    lines:
        HASH(0x4d1b840):
            length: 13
            offset: 13
        HASH(0x4d1df38):
            length: 5
            offset: 1
        HASH(0x4d1eee8): ~

Answer 1

您使用的Perl数据结构与您需要的YAML数据不对应。它只是偶然编译，你必须看到警告

匿名哈希中奇数个元素

执行代码时。请不要忽略警告，特别是在寻求代码帮助时

在YAML中，lines元素是一个数组，而您的Perl数据将其作为哈希。您需要用方括号{ ... }

替换大括号[...]

我还建议您避免YAML::Dump，这是YAML::Tiny模块的微观黑客攻击。 YAML::XS是YAML的首选Perl实现，是优秀libyaml库的绑定

Answer 2

这不是YAML问题; lines应映射到arrayref，而不是hashref：

text => {
     lines => { # this is an hashref, so
     {
         offset => 0,
         length => 1
     }, # this is a hash key, and gets stringified: "HASH(0x4d1df38)"
     {
         offset => 1,
         length => 5,
     }, # and this is a hash value
     {
         offset => 6,
         length => 7,
     }, # this is a key, also stringified: "HASH(0x4d1b840)"
     {
         offset => 13,
         length => 13,
     }, # and this is a value...
     {
         offset => 26,
         length => 1,
     }
     }
  }
};

从Perl数据结构序列化YAML文档

2 个答案: