Its quicker to fail on buggy json than RFC: A walkthrough from JSON ABNF to Regexp::Grammars 

sub fa {
    my $time = time;
    my $ref  = from_json(@_);
    $time = time-$time;
    print "T$time  ", Dumper( $ref ),"\n";
}


fa(q{["double extra comma",,]}); ## THE BUGGY
fa(q{[1,[2,[3],[]]]}); ## THE REGULAR
fa( q{[{"k":"v"},{"v":"k"}] } );
fa( q{{"ro":["sham","bo"],"t":{"i":{"c":{"t":{"o":"c"}}}}}} );
__END__
T5  $VAR1 = 'no match';

T0  $VAR1 = [
          1,
          [
            2,
            [
              3
            ],
            []
          ]
        ];

T0  $VAR1 = [
          {
            'k' => 'v'
          },
          {
            'v' => 'k'
          }
        ];

T0  $VAR1 = {
          'ro' => [
                    'sham',
                    'bo'
                  ],
          't' => {
                   'i' => {
                            'c' => {
                                     't' => {
                                              'o' => 'c'
                                            }
                                   }
                          }
                 }
        };

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In reply to Re: JSON parser as a single Perl Regex by Anonymous Monk
in thread JSON parser as a single Perl Regex by merlyn

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