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Mojo::JSON - Minimalistic JSON


  use Mojo::JSON qw(decode_json encode_json);

  my $bytes = encode_json {foo => [1, 2], bar => 'hello!', baz => \1};
  my $hash  = decode_json $bytes;


Mojo::JSON is a minimalistic and possibly the fastest pure-Perl implementation of RFC 8259.

It supports normal Perl data types like scalar, array reference, hash reference and will try to call the TO_JSON method on blessed references, or stringify them if it doesn't exist. Differentiating between strings and numbers in Perl is hard, depending on how it has been used, a scalar can be both at the same time. The string value has a higher precedence unless both representations are equivalent.

  [1, -2, 3]     -> [1, -2, 3]
  {"foo": "bar"} -> {foo => 'bar'}

Literal names will be translated to and from Mojo::JSON constants or a similar native Perl value.

  true  -> Mojo::JSON->true
  false -> Mojo::JSON->false
  null  -> undef

In addition scalar references will be used to generate booleans, based on if their values are true or false.

  \1 -> true
  \0 -> false

The character / will always be escaped to prevent XSS attacks.

  "</script>" -> "<\/script>"

For better performance the optional module Cpanel::JSON::XS (4.09+) will be used automatically if possible. This can also be disabled with the MOJO_NO_JSON_XS environment variable.


Mojo::JSON implements the following functions, which can be imported individually.


  my $value = decode_json $bytes;

Decode JSON to Perl value and die if decoding fails.


  my $bytes = encode_json {i => '♥ mojolicious'};

Encode Perl value to JSON.


  my $false = false;

False value, used because Perl has no native equivalent.


  my $value = from_json $chars;

Decode JSON text that is not UTF-8 encoded to Perl value and die if decoding fails.


  my $bytes = j [1, 2, 3];
  my $bytes = j {i => '♥ mojolicious'};
  my $value = j $bytes;

Encode Perl data structure (which may only be an array reference or hash reference) or decode JSON, an undef return value indicates a bare null or that decoding failed.


  my $chars = to_json {i => '♥ mojolicious'};

Encode Perl value to JSON text without UTF-8 encoding it.


  my $true = true;

True value, used because Perl has no native equivalent.


Mojolicious, Mojolicious::Guides,