Why is Dumper showing decoded JSON booleans like this?

nleaman has asked for the wisdom of the Perl Monks concerning the following question:

#!/usr/bin/perl -w
use strict;
use Data::Dumper;
use JSON;

# sample json data
my $json_text = <<END;
{
  "id": 559,
  "bool_one": false,
  "bool_two": false,
  "bool_three": false,
  "alertStates": ["OK"]
}
END
my $json_text_decoded = decode_json $json_text;
print Dumper $json_text_decoded ;
print "\n$json_text_decoded\n";
foreach (keys %{($json_text_decoded)}) {
    print " $_ = $$json_text_decoded{$_}\n";
}
[download]

OUTPUT:

$VAR1 = {
          'alertStates' => [
                             'OK'
                           ],
          'bool_two' => bless( do{\(my $o = 0)}, 'JSON::PP::Boolean' )
+,
          'bool_three' => $VAR1->{'bool_two'},
          'bool_one' => $VAR1->{'bool_two'},
          'id' => 559
        };

HASH(0x100873888)
 alertStates = ARRAY(0x1008739c0)
 bool_two = false
 bool_three = false
 bool_one = false
 id = 559
[download]

Comment on Why is Dumper showing decoded JSON booleans like this? Select or Download Code

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Re: Why is Dumper showing decoded JSON booleans like this? by ikegami (Patriarch) on Mar 03, 2010 at 18:08 UTC
Perl doesn't have a boolean type. In order to be able to do round trips, JSON uses an overloaded object to represent booleans.	[reply]
Re^2: Why is Dumper showing decoded JSON booleans like this? by nleaman (Initiate) on Mar 03, 2010 at 19:42 UTC
Okay. That makes sense. I guess my problem then becomes something different which is when using PHP::Serialization to serialize the decoded json text: `#!/usr/bin/perl -w use strict; use Data::Dumper; use JSON; use PHP::Serialization qw(serialize unserialize); my $json_text ='{ "boolean": true }'; my $json_text_decoded = decode_json $json_text; serialize($json_text_decoded);` [download] OUTPUT: `Not a HASH reference at lib/PHP/Serialization.pm line 454.` It dies when working on the object data type. Is there a straightforward way to convert the boolean object to a literal string?	[reply] [d/l] [select]
Re^3: Why is Dumper showing decoded JSON booleans like this? by ikegami (Patriarch) on Mar 03, 2010 at 20:18 UTC
You'll have to traverse the returned data structure, using JSON::is_bool to check for boolean nodes, replacing boolean nodes with the values of your choice. If PHP::Serialization supported custom object serializers, you could just write one of those for JSON::PP::Boolean, but it doesn't appear to be the case.	[reply]
Re^4: Why is Dumper showing decoded JSON booleans like this? by nleaman (Initiate) on Mar 04, 2010 at 21:01 UTC
Re: Why is Dumper showing decoded JSON booleans like this? by Anonymous Monk on Mar 03, 2010 at 18:11 UTC
Because that is what they are , and its Dumpers job? `BEGIN { package WhatItDoes; sub new { bless {}, shift } } use Data::Dumper; use CGI; print Dumper( { 6, CGI->new(''), 1 , WhatItDoes->new }); __END__ $VAR1 = { '6' => bless( { '.parameters' => [], 'use_tempfile' => 1, '.charset' => 'ISO-8859-1', '.fieldnames' => {}, 'param' => {}, 'escape' => 1 }, 'CGI' ), '1' => bless( {}, 'WhatItDoes' ) };` [download]	[reply] [d/l]