perl JSON 解码没有给出预期的结果

Question

我有以下 JSON 输入 -

{"links":{"self":"/some/path"},"data": [{"type":"some_service","id":"foo","attributes": {"created":true,"active":true,"suspended":false}}, {"type":"some_service","id":"dummy","attributes":{"created":false}}]}

我正在使用以下代码 -

use strict;
use warnings;
use JSON::XS;
use Data::Dumper;

my $result = decode_json($input);
print Dumper($result) . "\n";

但我的输出低于 -

$VAR1 = {
      'data' => [
                  {
                    'attributes' => {
                                      'active' => bless( do{\(my $o = 1)}, 'JSON::XS::Boolean' ),
                                      'created' => $VAR1->{'data'}[0]{'attributes'}{'active'},
                                      'suspended' => bless( do{\(my $o = 0)}, 'JSON::XS::Boolean' )
                                    },
                    'id' => 'foo',
                    'type' => 'some_service'
                  },
                  {
                    'id' => 'dummy',
                    'attributes' => {
                                      'created' => $VAR1->{'data'}[0]{'attributes'}{'suspended'}
                                    },
                    'type' => 'some_service'
                  }
                ],
      'links' => {
                   'self' => '/some/path'
                 }
    };

看起来 'created' 中的值是 $VAR1->{'data'}[0]{'attributes'}{'active'} 这似乎不是其他地方也准确无误。

我是不是遗漏了某处代码或者 JSON 输入有错误？请提供您的建议。

Answer 1

JSON 解码器只是 "mapping/pointing" 已经解析的先前值的值。您可以看到您的第一个 created 指向

$VAR1->{'data'}[0]{'attributes'}{'active'},

，其值为true，就像active应该的那样。您正在查看散列数组的 Data::Dumper 表示。

如果您要从 Perl 变量中检索一个元素，您会发现它与您的原始输入匹配：

print $result->{"data"}[0]->{"attributes"}->{"created"}; # prints 1

要在不发生这种情况的情况下打印 Data::Dumper 输出，只需在脚本中设置此标志：

$Data::Dumper::Deepcopy = 1;

Answer 2

为什么您认为它不准确？如果我们查看 JSON，active 和 created 都有相同的值：true。也许你会发现转储结构如下更清晰：

use JSON::XS     qw( decode_json );
use Data::Dumper qw( );

my $data = decode_json(<<'__EOI__');
{"links":{"self":"/some/path"},"data [{"type":"some_service","id":"foo","attributes": {"created":true,"active":true,"suspended":false}}, {"type":"some_service","id":"dummy","attributes":{"created":false}}]}
__EOI__

print(Data::Dumper->Dump(
   [ JSON::XS::true, JSON::XS::false, $data ],
   [qw( true false data )],
));

输出：

$true = bless( do{\(my $o = 1)}, 'JSON::PP::Boolean' );
$false = bless( do{\(my $o = 0)}, 'JSON::PP::Boolean' );
$data = {
          'data' => [
                      {
                        'attributes' => {
                                          'active' => $true,
                                          'created' => $true,
                                          'suspended' => $false
                                        },
                        'id' => 'foo',
                        'type' => 'some_service'
                      },
                      {
                        'attributes' => {
                                          'created' => $false
                                        },
                        'id' => 'dummy',
                        'type' => 'some_service'
                      }
                    ],
          'links' => {
                       'self' => '/some/path'
                     }
        };

perl JSON 解码没有给出预期的结果

perl JSON decode is not giving expected result

perl

json

data-dumper