JSON::backportPP(3)

📦

version 4.10 · 12 versions

4.10 · opensuse-leap 16.0 (latest)
4.03 · centos-stream 9
4.10 · centos-stream 10
4.10 · alpine 3.22
4.10 · alpine 3.23
4.10 · alpine 3.24
4.11 · arch rolling
4.10 · fedora 43
4.04000 · ubuntu jammy
4.10 · fedora 44
4.10000 · ubuntu noble, ubuntu resolute, ubuntu stonking
4.10000 · debian bookworm, debian trixie

💖 JSON::backportPP(3) 💖

okay bestie, so this is the manual page JSON::backportPP(3) — but the star of the show, the actual module, is JSON::PP. same energy, iykyk. pull up a chair 🎀

✨ NAME ✨

JSON::PP — the JSON::XS-compatible pure-Perl module. yes. pure Perl. no C compiler needed, we're doing this in the language itself 💅

✨ SYNOPSIS ✨

use JSON::PP;

# exported functions, they croak on error
# and expect/generate UTF-8

$utf8_encoded_json_text = encode_json $perl_hash_or_arrayref;
$perl_hash_or_arrayref  = decode_json $utf8_encoded_json_text;

# OO-interface

$json = JSON::PP->new->ascii->pretty->allow_nonref;

$pretty_printed_json_text = $json->encode( $perl_scalar );
$perl_scalar = $json->decode( $json_text );

# Note that JSON version 2.0 and above will automatically use
# JSON::XS or JSON::PP, so you should be able to just:

use JSON;

like, the last one is the real protagonist moment ngl — from JSON version 2.0 and above it'll automatically pick JSON::XS or JSON::PP for you, so a plain use JSON; just works 🫶

✨ DESCRIPTION ✨

So JSON::PP is a pure Perl JSON decoder/encoder, and it's (almost) compatible with the much faster JSON::XS, which Marc Lehmann wrote in C. JSON::PP is the fallback module that kicks in when you use JSON but haven't installed JSON::XS — main character energy as a safety net, honestly 🦋

Because of that fallback thing in JSON.pm, JSON::PP tries not to be more JavaScript-friendly than JSON::XS — like, it deliberately doesn't escape extra characters such as U+2028 and U+2029, etc. — so you don't silently lose that JavaScript-friendliness when you use JSON.pm and then install JSON::XS either for speed or by accident 🙈 If you genuinely need a JavaScript-friendly RFC7159-compliant pure perl module, go try JSON::Tiny — it's derived from the Mojolicious web framework and is also smaller and faster than JSON::PP. slay for it.

JSON::PP has been in the Perl core since Perl 5.14, mainly so CPAN toolchain modules can parse META.json. it's giving "institutional legend" 👑

✨ FUNCTIONAL INTERFACE ✨

This section is taken from JSON::XS almost verbatim (respect where it's due 🌸). Both encode_json and decode_json are exported by default. free functions, no object required, we love a low-effort moment.

🎀 encode_json

$json_text = encode_json $perl_scalar

Converts the Perl data structure you hand it into a UTF-8 encoded, binary string — meaning the string contains octets only, no fancy characters, just bytes. It croaks on error 😭

This function call is functionally identical to:

$json_text = JSON::PP->new->utf8->encode($perl_scalar)

Except being faster. ⚡

🎀 decode_json

$perl_scalar = decode_json $json_text

The opposite of encode_json (iconic symmetry ✨): it expects a UTF-8 (binary) string and tries to parse that as a UTF-8 encoded JSON text, then returns the resulting reference. It also croaks on error 😭

This function call is functionally identical to:

$perl_scalar = JSON::PP->new->utf8->decode($json_text)

Except being faster. ⚡

🎀 JSON::PP::is_bool

$is_boolean = JSON::PP::is_bool($scalar)

Returns true if the scalar you passed in represents either JSON::PP::true or JSON::PP::false — those two lil constants that act like 1 and 0 respectively, and which are also used to represent JSON true and false in Perl strings. cute, right? 🍓

On perl 5.36 and above, it will also return true when you give it one of perl's standard boolean values, like the result of a comparison. so your $a == $b output counts too, no cap.

See MAPPING, below, for more info on how JSON values get mapped to Perl. 👀

✨ OBJECT-ORIENTED INTERFACE ✨

This section is also taken from JSON::XS. (they're basically siblings, we stan a family business 💜)

The object oriented interface is your moment to configure your own encoding or decoding style, within the limits of the supported formats. you're the main character, but the format has rules, bestie.

🦋 new

$json = JSON::PP->new

Creates a fresh new JSON::PP object that you can use to de/encode JSON strings. All the boolean flags described below are disabled by default — with the one exception of allow_nonref, which defaults to enabled since version 4.0. slay for the exception.

Oh and the mutators for flags all return the JSON::PP object again, so you can chain calls like a absolute queen:

my $json = JSON::PP->new->utf8->space_after->encode({a => [1,2]})
=> {"a": [1, 2]}

look at that chaining. flawless. 💅

🦋 ascii

$json = $json->ascii([$enable])

$enabled = $json->get_ascii

If $enable is true (or you just leave it missing), then the encode method will not generate characters outside the code range 0..127 — that's ASCII, the OG. Any Unicode characters outside that range get escaped using either a single \uXXXX (for BMP characters) or a double \uHHHH\uLLLLL escape sequence, as per RFC4627. The resulting encoded JSON text can be treated as a native Unicode string, an ascii-encoded string, a latin1-encoded string, a UTF-8 encoded string, or literally any other superset of ASCII. versatile icon ✨

If $enable is false, then encode will not escape Unicode characters unless the JSON syntax or other flags require it. This gives you a faster and more compact format. 🏎️

See also the section ENCODING/CODESET FLAG NOTES later in this document.

The main use for this flag is to produce JSON texts that can be transmitted over a 7-bit channel, since the encoded JSON texts won't contain any 8 bit characters. periodt.

JSON::PP->new->ascii(1)->encode([chr 0x10401])
=> ["\ud801\udc01"]

🦋 latin1

$json = $json->latin1([$enable])

$enabled = $json->get_latin1

If $enable is true (or missing), then the encode method will encode the resulting JSON text as latin1 (or iso-8859-1), escaping any characters outside the code range 0..255. That resulting string can be treated as a latin1-encoded JSON text or as a native Unicode string. The decode method is not affected in any way by this flag, because decode by default expects Unicode, which is a strict superset of latin1. it's giving "not my problem" 🙈

If $enable is false, then encode won't escape Unicode characters unless the JSON syntax or other flags require it.

See also the section ENCODING/CODESET FLAG NOTES later in this document.

The main use for this flag is efficiently encoding binary data as JSON text, because most octets won't be escaped, which results in a smaller encoded size. the downside? the resulting JSON text is encoded in latin1 (and must correctly be treated as such when you store and transfer it), and latin1 is a rare encoding for JSON. So it's most useful when you want to store data structures that you know contain binary data efficiently in files or databases — not when you're talking to other JSON encoders/decoders. talk to them in something normal, bestie.

JSON::PP->new->latin1->encode (["\x{89}\x{abc}"]
=> ["\x{89}\\u0abc"]    # (perl syntax, U+abc escaped, U+89 not)

🦋 utf8

$json = $json->utf8([$enable])

$enabled = $json->get_utf8

If $enable is true (or missing), then the encode method will encode the JSON result into UTF-8, as required by many protocols, while the decode method expects to be handed a UTF-8-encoded string. Please note that UTF-8-encoded strings don't contain any characters outside the range 0..255 — that's exactly why they're so useful for bytewise/binary I/O 💾 In future versions, enabling this option might enable autodetection of the UTF-16 and UTF-32 encoding families, as described in RFC4627. (might! no promises! don't come for me.)

If $enable is false, then encode will return the JSON string as a (non-encoded) Unicode string, while decode expects a Unicode string. Any decoding or encoding (e.g. to UTF-8 or UTF-16) is on you — do it yourself, e.g. with the Encode module. DIY era 🛠️

See also the section ENCODING/CODESET FLAG NOTES later in this document.

Example, output UTF-16BE-encoded JSON:

use Encode;
$jsontext = encode "UTF-16BE", JSON::PP->new->encode ($object);

Example, decode UTF-32LE-encoded JSON:

use Encode;
$object = JSON::PP->new->decode (decode "UTF-32LE", $jsontext);

🦋 pretty

$json = $json->pretty([$enable])

This enables (or disables) all of the indent, space_before and space_after flags — and possibly more in the future — in one single call, so you get the most readable (or the most compact) form possible. one button, whole glow-up 🌈

🦋 indent

$json = $json->indent([$enable])

$enabled = $json->get_indent

If $enable is true (or missing), then the encode method uses a multiline format as output, putting every array member or object/hash key-value pair on its own line, indenting them properly. aesthetic. organised. 💅

If $enable is false, no newlines or indenting get produced, and the resulting JSON text is guaranteed not to contain any "newlines".

This setting has no effect when decoding JSON texts.

The default indent space length is three. You can use indent_length to change that length. (yes, three. not four. not two. three. respect it.)

🦋 space_before

$json = $json->space_before([$enable])

$enabled = $json->get_space_before

If $enable is true (or missing), then encode will add an extra optional space before the ":" that separates keys from values in JSON objects. lil breathing room, we love to see it 🫶

If $enable is false, then encode won't add any extra space at those places. tight. compact. efficient.

This setting has no effect when decoding JSON texts. You'll also most likely want to combine this setting with space_after.

Example, space_before enabled, space_after and indent disabled:

{"key" :"value"}

🦋 space_after

$json = $json->space_after([$enable])

$enabled = $json->get_space_after

If $enable is true (or missing), then encode will add an extra optional space after the ":" separating keys from values in JSON objects, plus extra whitespace after the "," that separates key-value pairs and array members. both sides get love ✨

If $enable is false, then encode won't add any extra space at those places.

This setting has no effect when decoding JSON texts.

Example, space_before and indent disabled, space_after enabled:

{"key": "value"}

🦋 relaxed

$json = $json->relaxed([$enable])

$enabled = $json->get_relaxed

If $enable is true (or missing), then decode will accept some extensions to normal JSON syntax (see below). encode is not affected in any way. ⚠️ BE AWARE that this option makes you accept invalid JSON texts as if they were valid! I suggest only using this option to parse application-specific files written by humans — configuration files, resource files, etc. it's the "chill mode" of parsing and chill mode has consequences 😭

If $enable is false (the default), then decode will only accept valid JSON texts. strict queen 👑

Currently accepted extensions are:

list items can have an end-comma

JSON separates array elements and key-value pairs with commas. This can be annoying if you write JSON texts manually and want to be able to quickly append elements, so this extension accepts a comma at the end of such items, not just between them:

[
   1,
   2, <- this comma not normally allowed
]
{
   "k1": "v1",
   "k2": "v2", <- this comma not normally allowed
}

shell-style '#'-comments

Whenever JSON allows whitespace, shell-style comments are additionally allowed. They're terminated by the first carriage-return or line-feed character, after which more white-space and comments are allowed.

[
   1, # this comment not allowed in JSON
      # neither this one...
]

C-style multiple-line '/* */'-comments (JSON::PP only)

Whenever JSON allows whitespace, C-style multiple-line comments are additionally allowed. Everything between /* and */ is a comment, after which more white-space and comments are allowed.

  [
     1, /* this comment not allowed in JSON */
        /* neither this one... */
  ]

C++-style one-line // comments — JSON::PP only, bestie 💅

Whenever JSON allows whitespace, C++-style one-line comments are additionally allowed. They are terminated by the first carriage-return or line-feed character, after which more white-space and comments are allowed. Obsessed tbh.

[
   1, // this comment not allowed in JSON
      // neither this one...
]

literal ASCII TAB characters in strings 🌸

Literal ASCII TAB characters are now allowed in strings (and treated as "\t"). Yes, icon behaviour.

[
   "Hello\tWorld",
   "Hello<TAB>World", # literal <TAB> would not normally be allowed
]

canonical 🎀

$json = $json->canonical([$enable])

$enabled = $json->get_canonical

If $enable is true (or missing), then the encode method will output JSON objects by sorting their keys. Heads up: this is adding a comparatively high overhead. Like, it's not free, bestie 💸

If $enable is false, then the encode method will output key-value pairs in the order Perl stores them (which will likely change between runs of the same script, and can change even within the same run from 5.18 onwards). Chaos, honestly 😭

This option is useful if you want the same data structure to be encoded as the same JSON text (given the same overall settings). If it is disabled, the same hash might be encoded differently even if it contains the same data, as key-value pairs have no inherent ordering in Perl. Fr, hashes are just Like That.

This setting has no effect when decoding JSON texts. ✨

This setting has currently no effect on tied hashes.

allow_nonref 🌈

$json = $json->allow_nonref([$enable])

$enabled = $json->get_allow_nonref

Okay so unlike all the other boolean options, this one is enabled by default beginning with version 4.0. Main character energy 👑

If $enable is true (or missing), then the encode method can convert a non-reference into its corresponding string, number or null JSON value, which is an extension to RFC4627. Likewise, decode will accept those JSON values instead of croaking. Slay.

If $enable is false, then the encode method will croak if it isn't passed an arrayref or hashref, as JSON texts must either be an object or array. Likewise, decode will croak if given something that is not a JSON object or array. No vibes allowed, apparently 💀

Example, encode a Perl scalar as JSON value without enabled allow_nonref, resulting in an error:

JSON::PP->new->allow_nonref(0)->encode ("Hello, World!")
=> hash- or arrayref expected...

allow_unknown 🫶

$json = $json->allow_unknown([$enable])

$enabled = $json->get_allow_unknown

If $enable is true (or missing), then encode will not throw an exception when it encounters values it cannot represent in JSON (for example, filehandles) but instead will encode a JSON null value. Note that blessed objects are not included here and are handled separately by c<allow_blessed>. Different department, iykyk.

If $enable is false (the default), then encode will throw an exception when it encounters anything it cannot encode as JSON. Gagged, but fair.

This option does not affect decode in any way, and it is recommended to leave it off unless you know your communications partner. Stranger danger, bestie 🙈

allow_blessed 💜

$json = $json->allow_blessed([$enable])

$enabled = $json->get_allow_blessed

See "OBJECT SERIALISATION" for details.

If $enable is true (or missing), then the encode method will not barf when it encounters a blessed reference that it cannot convert otherwise. Instead, a JSON null value is encoded instead of the object. It just shrugs and moves on 💅

If $enable is false (the default), then encode will throw an exception when it encounters a blessed object that it cannot convert otherwise.

This setting has no effect on decode. Zero. Nada.

convert_blessed 🦋

$json = $json->convert_blessed([$enable])

$enabled = $json->get_convert_blessed

See "OBJECT SERIALISATION" for details.

If $enable is true (or missing), then encode, upon encountering a blessed object, will check for the availability of the TO_JSON method on the object's class. If found, it will be called in scalar context and the resulting scalar will be encoded instead of the object. Iconic conversion pipeline ✨

The TO_JSON method may safely call die if it wants. If TO_JSON returns other blessed objects, those will be handled in the same way. TO_JSON must take care of not causing an endless recursion cycle (== crash) in this case. Like, fr fr, watch out for that one — infinite recursion is not the vibe, it's a crash 💀 The name of TO_JSON was chosen because other methods called by the Perl core (== not by the user of the object) are usually in upper case letters and to avoid collisions with any to_json function or method. Cute lore drop 🎀

If $enable is false (the default), then encode will not consider this type of conversion.

This setting has no effect on decode.

allow_tags 🍓

$json = $json->allow_tags([$enable])

$enabled = $json->get_allow_tags

See "OBJECT SERIALISATION" for details.

If $enable is true (or missing), then encode, upon encountering a blessed object, will check for the availability of the FREEZE method on the object's class. If found, it will be used to serialise the object into a nonstandard tagged JSON value (that JSON decoders cannot decode). Yeah, it's nonstandard — regular JSON decoders literally cannot decode it, so know what you're signing up for 🫠

It also causes decode to parse such tagged JSON values and deserialise them via a call to the THAW method. The full pipeline, bestie 🌈

If $enable is false (the default), then encode will not consider this type of conversion, and tagged JSON values will cause a parse error in decode, as if tags were not part of the grammar. Strict mode stays strict.

boolean_values ⭐

$json->boolean_values([$false, $true])

($false,  $true) = $json->get_boolean_values

By default, JSON booleans will be decoded as overloaded $JSON::PP::false and $JSON::PP::true objects. The default cuties 💖

With this method you can specify your own boolean values for decoding — on decode, JSON false will be decoded as a copy of $false, and JSON true will be decoded as $true ("copy" here is the same thing as assigning a value to another variable, i.e. $copy = $false). Customise away 👑

This is useful when you want to pass a decoded data structure directly to other serialisers like YAML, Data::MessagePack and so on. Interop moment 🤝

Note that this works only when you decode. You can set incompatible boolean objects (like boolean), but when you encode a data structure with such boolean objects, you still need to enable convert_blessed (and add a TO_JSON method if necessary). Read that twice, bestie, it's giving gotcha 🙈

Calling this method without any arguments will reset the booleans to their default values. Ctrl+Z for booleans ✨

get_boolean_values will return both $false and $true values, or the empty list when they are set to the default.

core_bools 🔥

$json->core_bools([$enable]);

If $enable is true (or missing), then decode, will produce standard perl boolean values. Equivalent to calling:

$json->boolean_values(!!1, !!0)

get_core_bools will return true if this has been set. On perl 5.36, it will also return true if the boolean values have been set to perl's core booleans using the boolean_values method. Version-specific behaviour, we love to see it 💅

The methods unblessed_bool and get_unblessed_bool are provided as aliases for compatibility with Cpanel::JSON::XS. Aliases, so you don't get confused — thoughtful fr 🫶

filter_json_object 🌸

$json = $json->filter_json_object([$coderef])

When $coderef is specified, it will be called from decode each time it decodes a JSON object. The only argument is a reference to the newly-created hash. If the code references returns a single scalar (which need not be a reference), this value (or rather a copy of it) is inserted into the deserialised data structure. If it returns an empty list (NOTE: not undef, which is a valid scalar), the original deserialised hash will be inserted. This setting can slow down decoding considerably. Performance said "not today" 😭

When $coderef is omitted or undefined, any existing callback will be removed and decode will not change the deserialised hash in any way.

Example, convert all JSON objects into the integer 5:

my $js = JSON::PP->new->filter_json_object(sub { 5 });
# returns [5]
$js->decode('[{}]');
# returns 5
$js->decode('{"a":1, "b":2}');

filter_json_single_key_object 🧚

$json = $json->filter_json_single_key_object($key [=> $coderef])

Works remotely similar to filter_json_object, but is only called for JSON objects having a single key named $key. Targetted. Focused. Iconic 🎯

This $coderef is called before the one specified via filter_json_object, if any. It gets passed the single value in the JSON object. If it returns a single value, it will be inserted into the data structure. If it returns nothing (not even undef but the empty list), the callback from filter_json_object will be called next, as if no single-key callback were specified. Chain of command, bestie 💅

If $coderef is omitted or undefined, the corresponding callback will be disabled. There can only ever be one callback for a given key. One (1) callback. Periodt.

As this callback gets called less often then the filter_json_object one, decoding speed will not usually suffer as much. Therefore, single-key objects make excellent targets to serialise Perl objects into, especially as single-key JSON objects are as close to the type-tagged value concept as JSON gets (it's basically an ID/VALUE tuple). Of course, JSON does not support this in any way, so you need to make sure your data never looks like a serialised Perl hash. Like genuinely make sure — this is on you, not on JSON 🙈

Typical names for the single object key are "__class_whatever__", or "$__dollars_are_rarely_used__$" or "}ugly_brace_placement", or even things like "__class_md5sum(classname)__", to reduce the risk of clashing with real hashes. Ugly on purpose, that's the whole point 🎀

Example, decode JSON objects of the form { "__widget__" => <id> } into the corresponding $WIDGET{<id>} object:

# return whatever is in $WIDGET{5}:
JSON::PP
   ->new
   ->filter_json_single_key_object (__widget__ => sub {
         $WIDGET{ $_[0] }
      })
   ->decode ('{"__widget__": 5')

# this can be used with a TO_JSON method in some "widget" class
# for serialisation to json:
sub WidgetBase::TO_JSON {
   my ($self) = @_;

   unless ($self->{id}) {
      $self->{id} = ..get..some..id..;
      $WIDGET{$self->{id}} = $self;
   }

   { __widget__ => $self->{id} }
}

shrink 🦋

$json = $json->shrink([$enable])

$enabled = $json->get_shrink

If $enable is true (or missing), the string returned by encode will be shrunk (i.e. downgraded if possible). Glow-down for strings ✨

The actual definition of what shrink does might change in future versions, but it will always try to save space at the expense of time. Trade-offs, bestie — space over time, always 💅

If $enable is false, then JSON::PP does nothing. It simply does not perceive it.

max_depth 🎀

$json = $json->max_depth([$maximum_nesting_depth])

$max_depth = $json->get_max_depth

Nesting level is literally just how many hashrefs or arrayrefs the encoder has to walk through to reach a point — or, in a string, how many { or [ characters you've passed without meeting their matching closing paren. That's it, that's the metric 🎀

Set it to one and you're saying "no nesting, periodt" — so the thing has to be a single lone hash/object or a single array. Iconic minimalism.

If you pass no argument at all, it uses the highest possible setting, which… ngl, is rarely useful 🙈

Wanna know why any of this matters? Go read "SECURITY CONSIDERATIONS" in JSON::XS — it explains the whole vibe. 🛡️

🌸 max_size 🌸

$json = $json->max_size([$maximum_string_size])

$max_size = $json->get_max_size

This one caps how many bytes a JSON text is allowed to be while decoding is happening. Default is 0, which means no limit — live free, decode wild 🦋

So when decode gets called on a string that's longer than this many bytes, it won't even try. It just throws an exception at you. Rude but efficient 😭

Heads up though: this setting currently has no effect on encode (yet). Encode does what it wants 💅

No argument given? Then the limit check gets deactivated — same as passing 0. ✨

Again, for the why, peep "SECURITY CONSIDERATIONS" in JSON::XS 🫶

💖 encode 💖

$json_text = $json->encode($perl_scalar)

Takes your Perl value or data structure and converts it into its JSON glow-up. Croaks on error — so if it's mad, you'll know 🔥

💜 decode 💜

$perl_scalar = $json->decode($json_text)

The literal opposite of "encode": hand it a JSON text, it tries to parse it, and gives you back the resulting simple scalar or reference. Croaks on error, same energy 💀

🦋 decode_prefix 🦋

($perl_scalar, $characters) = $json->decode_prefix($json_text)

Works like "decode", except instead of throwing an exception when there's trailing garbage after the first JSON object, it just silently stops parsing right there and hands you back how many characters it consumed so far. Chill about it, honestly 🙈

Super useful when your JSON texts aren't delimited by some outer protocol and you genuinely need to know where the JSON ends. iykyk 🎀

JSON::PP->new->decode_prefix ("[1] the tail")
=> ([1], 3)

✨ FLAGS FOR JSON::PP ONLY ✨

Okay bestie, listen. Everything below this line is JSON::PP only — like, exclusive, members-only, VIP section 🎟️

Which means: if you use any of these, you cannot make your app run faster by swapping JSON::PP out for JSON::XS. Not happening. 🙅‍♀️

Need these and the speed boost? You might wanna try Cpanel::JSON::XS, a fork of JSON::XS by Reini Urban, which supports some of these — though with a different set of incompatibilities. Pick your chaos 🌈

Fr fr though: most of these historical flags are only kept around for backward compatibility and should NOT be used in a new application. Periodt. 💅

🎀 allow_singlequote 🎀

$json = $json->allow_singlequote([$enable])
$enabled = $json->get_allow_singlequote

If $enable is true (or missing), then "decode" will accept invalid JSON texts containing strings that begin and end with single quotation marks. "encode" is completely unbothered by this — not affected in any way 💅

⚠️ Be aware that this option makes you accept invalid JSON texts as if they were valid!! I suggest only using it to parse application-specific files written by humans — configuration files, resource files, that whole genre 📁

If $enable is false (the default), then "decode" only accepts valid JSON texts. Good girl behaviour ✨

$json->allow_singlequote->decode(qq|{"foo":'bar'}|);
$json->allow_singlequote->decode(qq|{'foo':"bar"}|);
$json->allow_singlequote->decode(qq|{'foo':'bar'}|);

🌸 allow_barekey 🌸

$json = $json->allow_barekey([$enable])
$enabled = $json->get_allow_barekey

If $enable is true (or missing), "decode" will accept invalid JSON texts where JSON object names don't begin and end with quotation marks. "encode"? Unaffected, bestie, it's not even watching 💅

⚠️ Again: this makes you accept invalid JSON as if it were valid! Only use it for application-specific human-written files (config files, resource files, etc.) 🙈

If $enable is false (the default), "decode" only accepts valid JSON texts. 🦋

$json->allow_barekey->decode(qq|{foo:"bar"}|);

💜 allow_bignum 💜

$json = $json->allow_bignum([$enable])
$enabled = $json->get_allow_bignum

If $enable is true (or missing), "decode" will convert big integers Perl can't handle as integers into Math::BigInt objects, and convert floating numbers into Math::BigFloat objects. Then "encode" converts "Math::BigInt" and "Math::BigFloat" objects back into JSON numbers. Round trip, slay 🔥

$json->allow_nonref->allow_bignum;
$bigfloat = $json->decode('2.000000000000000000000000001');
print $json->encode($bigfloat);
# => 2.000000000000000000000000001

Also go peek at MAPPING for more on this one 👀

🦋 loose 🦋

$json = $json->loose([$enable])
$enabled = $json->get_loose

If $enable is true (or missing), "decode" accepts invalid JSON texts that contain unescaped [\x00-\x1f\x22\x5c] characters. "encode" is not affected in any way 💅

⚠️ Yes, same warning, it's important: this makes you accept invalid JSON texts as if they were valid! Only use it to parse application-specific files written by humans — config files, resource files, etc. 🙈

If $enable is false (the default), "decode" only accepts valid JSON texts ✨

$json->loose->decode(qq|["abc
                                       def"]|);

💖 escape_slash 💖

$json = $json->escape_slash([$enable])
$enabled = $json->get_escape_slash

If $enable is true (or missing), then "encode" will explicitly escape slash (solidus; U+002F) characters. Why? To reduce the risk of XSS (cross site scripting) that could be caused by </script> sitting inside a JSON text 💀 The cost? Your JSON texts get bloated in size. Trade-offs, bestie 🎀

This option might be useful when you embed JSON in HTML — but honestly, embedding arbitrary JSON in HTML (by some HTML template toolkit or by string interpolation) is risky in general. You must escape the necessary characters in the correct order, depending on the context. No shortcuts 🙅‍♀️

"decode" will not be affected in any way. Not even a little. 💅

🌈 indent_length 🌈

$json = $json->indent_length($number_of_spaces)
$length = $json->get_indent_length

Only useful when you also enable "indent" or "pretty". Got it? Got it. ✨

Here's the tea: JSON::XS indents with three spaces when you "encode" (if you asked for it via "indent" or "pretty"), and that number is not changeable. Period. JSON::PP, however, lets you change/get the number of indent spaces with this here mutator/accessor 👑

Default is three (same as JSON::XS), and the acceptable range is from 0 (no indentation — though honestly it'd be better to just disable indentation via indent(0)) all the way up to 15. Fifteen. Go off, I guess 💅

🍓 sort_by 🍓

$json = $json->sort_by($code_ref)
$json = $json->sort_by($subroutine_name)

If all you want is to sort keys (names) in JSON objects when you "encode", just enable the "canonical" option (see above) — that sorts object keys alphabetically, done, easy 🎀

But if you need to sort non-alphabetically for whatever reason, you can hand a code reference (or a subroutine name) to "sort_by", and then that argument gets passed to Perl's built-in sort function. Custom sorting, your rules 👑

Heads up though: because the sorting happens in the JSON::PP scope, you usually have to prepend JSON::PP:: to the subroutine name, and to the special variables $a and $b that sort uses inside the sub. It's giving namespace custody battle 😭

Example:

my %ORDER = (id => 1, class => 2, name => 3);
$json->sort_by(sub {
    ($ORDER{$JSON::PP::a} // 999) <=> ($ORDER{$JSON::PP::b} // 999)
    or $JSON::PP::a cmp $JSON::PP::b
});
print $json->encode([
    {name => 'CPAN', id => 1, href => 'http://cpan.org'}
]);
# [{"id":1,"name":"CPAN","href":"http://cpan.org"}]

⚠️ Note that "sort_by" affects all the plain hashes in the data structure. Every single one. If you need finer control, "tie" the necessary hashes with a module that implements an ordered hash (like Hash::Ordered and Tie::IxHash). And btw — "canonical" and "sort_by" do not affect the key order in "tie"d hashes 💅

use Hash::Ordered;
tie my %hash, 'Hash::Ordered',
    (name => 'CPAN', id => 1, href => 'http://cpan.org');
print $json->encode([\%hash]);
# [{"name":"CPAN","id":1,"href":"http://cpan.org"}] # order is kept

Look at that order being kept. We love to see it 🌸

✨ INCREMENTAL PARSING ✨

Okay so this section is also taken from JSON::XS, bestie.

Sometimes you lowkey need to parse JSON texts incrementally. This module always has to keep both the JSON text and the resulting Perl data structure in memory at one time, but it does let you parse a JSON stream incrementally. It does this by accumulating text until it has a full JSON object, which it can then decode. It’s similar to using decode_prefix to see if a full JSON object is available, but it’s much more efficient (and can be implemented with a minimum of method calls). Slay.

JSON::PP will only attempt to parse the JSON text once it’s sure it has enough text to get a decisive result, using a very simple but truly incremental parser. That means it sometimes won’t stop as early as the full parser — for example, it doesn’t detect mismatched parentheses. The only thing it guarantees is that it starts decoding as soon as a syntactically valid JSON text has been seen. So you need to set resource limits (e.g. max_size) to ensure the parser will stop parsing in the presence of syntax errors. No cap.

The following methods implement this incremental parser.

💅 incr_parse 💅

$json->incr_parse( [$string] ) # void context

$obj_or_undef = $json->incr_parse( [$string] ) # scalar context

@obj_or_empty = $json->incr_parse( [$string] ) # list context

This is the central parsing function, the main character of incremental parsing. It can both append new text and extract objects from the stream accumulated so far — both of these functions are optional.

If $string is given, then this string is appended to the already existing JSON fragment stored in the $json object.

After that, if the function is called in void context, it will simply return without doing anything further. This can be used to add more text in as many chunks as you want.

If the method is called in scalar context, then it will try to extract exactly one JSON object. If that’s successful, it will return this object; otherwise it will return undef. If there is a parse error, this method will croak just as decode would do (one can then use incr_skip to skip the erroneous part). This is the most common way of using the method.

And finally, in list context, it will try to extract as many objects from the stream as it can find and return them, or the empty list otherwise. For this to work, there must be no separators (other than whitespace) between the JSON objects or arrays — instead they must be concatenated back-to-back. If an error occurs, an exception will be raised as in the scalar context case. Note that in this case, any previously-parsed JSON texts will be lost. 😭

Example: parse some JSON arrays/objects in a given string and return them.

my @objs = JSON::PP->new->incr_parse ("[5][7][1,2]");

🎀 incr_text 🎀

$lvalue_string = $json->incr_text

This method returns the currently stored JSON fragment as an lvalue, meaning you can manipulate it. This only works when a preceding call to incr_parse in scalar context successfully returned an object. Under all other circumstances you must not call this function.

I mean it. Although in simple tests it might actually work, it will fail under real world conditions. 💀

As a special exception, you can also call this method before having parsed anything.

That means you can only use this function to look at or manipulate text before or after complete JSON objects, not while the parser is in the middle of parsing a JSON object.

This function is useful in two cases: a) finding the trailing text after a JSON object, or b) parsing multiple JSON objects separated by non-JSON text (such as commas).

🦋 incr_skip 🦋

$json->incr_skip

This will reset the state of the incremental parser and will remove the parsed text from the input buffer so far. This is useful after incr_parse died, in which case the input buffer and incremental parser state is left unchanged, to skip the text parsed so far and to reset the parse state.

The difference to incr_reset is that only text until the parse error occurred is removed.

🌈 incr_reset 🌈

$json->incr_reset

This completely resets the incremental parser — that is, after this call, it will be as if the parser had never parsed anything.

This is useful if you want to repeatedly parse JSON objects and want to ignore any trailing data, which means you have to reset the parser after each successful decode.

🗺️ MAPPING 🗺️

Most of this section is also taken from JSON::XS.

This section describes how JSON::PP maps Perl values to JSON values and vice versa. These mappings are designed to “do the right thing” in most circumstances automatically, preserving round-tripping characteristics (what you put in comes out as something equivalent). Obsessed.

For the more enlightened: note that in the following descriptions, lowercase perl refers to the Perl interpreter, while uppercase Perl refers to the abstract Perl language itself.

🔁 JSON -> PERL 🔁

🌸 object 🌸

A JSON object becomes a reference to a hash in Perl. No ordering of object keys is preserved (JSON does not preserve object key ordering itself).

🍓 array 🍓

A JSON array becomes a reference to an array in Perl.

🧚 string 🧚

A JSON string becomes a string scalar in Perl — Unicode codepoints in JSON are represented by the same codepoints in the Perl string, so no manual decoding is necessary.

🔥 number 🔥

A JSON number becomes either an integer, numeric (floating point) or string scalar in perl, depending on its range and any fractional parts. On the Perl level, there is no difference between those as Perl handles all the conversion details, but an integer may take slightly less memory and might represent more values exactly than floating point numbers.

If the number consists of digits only, JSON::PP will try to represent it as an integer value. If that fails, it will try to represent it as a numeric (floating point) value if that is possible without loss of precision. Otherwise it will preserve the number as a string value (in which case you lose roundtripping ability, as the JSON number will be re-encoded to a JSON string).

Numbers containing a fractional or exponential part will always be represented as numeric (floating point) values, possibly at a loss of precision (in which case you might lose perfect roundtripping ability, but the JSON number will still be re-encoded as a JSON number).

Note that precision is not accuracy — binary floating point values cannot represent most decimal fractions exactly, and when converting from and to floating point, JSON::PP only guarantees precision up to but not including the least significant bit.

When allow_bignum is enabled, big integer values and any numeric values will be converted into Math::BigInt and Math::BigFloat objects respectively, without becoming string scalars or losing precision.

✅ true, false ✅

These JSON atoms become JSON::PP::true and JSON::PP::false, respectively. They are overloaded to act almost exactly like the numbers 1 and 0. You can check whether a scalar is a JSON boolean by using the JSON::PP::is_bool function.

🫧 null 🫧

A JSON null atom becomes undef in Perl.

💬 shell-style comments (`# text`) 💬

As a nonstandard extension to the JSON syntax that is enabled by the relaxed setting, shell-style comments are allowed. They can start anywhere outside strings and go till the end of the line.

🏷️ tagged values (`(tag)value`) 🏷️

Another nonstandard extension to the JSON syntax, enabled with the allow_tags setting, is tagged values. In this implementation, the tag must be a perl package/class name encoded as a JSON string, and the value must be a JSON array encoding optional constructor arguments.

See “OBJECT SERIALISATION”, below, for details.

🪄 PERL -> JSON 🪄

The mapping from Perl to JSON is slightly more difficult, as Perl is a truly typeless language, so we can only guess which JSON type is meant by a Perl value.

👑 hash references 👑

Perl hash references become JSON objects. As there is no inherent ordering in hash keys (or JSON objects), they will usually be encoded in a pseudo-random order. JSON::PP can optionally sort the hash keys (determined by the canonical flag and/or sort_by property), so the same data structure will serialise to the same JSON text (given same settings and version of JSON::PP), but this incurs a runtime overhead and is only rarely useful, e.g. when you want to compare some JSON text against another for equality.

🌟 array references 🌟

Perl array references become JSON arrays.

🌀 other references 🌀

Other unblessed references are generally not allowed and will cause an exception to be thrown, except for references to the integers 0 and 1, which get turned into false and true atoms in JSON. You can also use JSON::PP::false and JSON::PP::true to improve readability.

to_json [\0, JSON::PP::true]      # yields [false,true]

💖 `JSON::PP::true`, `JSON::PP::false` 💖

These special values become JSON true and JSON false values, respectively. You can also use \1 and \0 directly if you want.

🌙 `JSON::PP::null` 🌙

This special value becomes JSON null.

🎁 blessed objects 🎁

Blessed objects are not directly representable in JSON, but JSON::PP allows various ways of handling objects. See “OBJECT SERIALISATION”, below, for details.

🧸 simple scalars 🧸

Simple Perl scalars (any scalar that is not a reference) are the most difficult objects to encode: JSON::PP will encode undefined scalars as JSON null values, scalars that have last been used in a string context before encoding as JSON strings, and anything else as number value.

# dump as number
encode_json [2]                      # yields [2]
encode_json [-3.0e17]                # yields [-3e+17]
my $value = 5; encode_json [$value]  # yields [5]

# used as string, so dump as string
print $value;
encode_json [$value]                 # yields ["5"]

# undef becomes null
encode_json [undef]                  # yields [null]

You can force the type to be a JSON string by stringifying it:

my $x = 3.1; # some variable containing a number
"$x";        # stringified
$x .= "";    # another, more awkward way to stringify
print $x;    # perl does it for you, too, quite often
             # (but for older perls)

You can force the type to be a JSON number by numifying it:

my $x = "3"; # some variable containing a string
$x += 0;     # numify it, ensuring it will be dumped as a number
$x *= 1;     # same thing, the choice is yours.

And that's genuinely it bestie — you literally can not currently force the type in other, less obscure, ways. 💅

Since version 2.91_01, JSON::PP uses a different number detection logic that converts a scalar that is possible to turn into a number safely. The new logic is slightly faster, and it tends to help people who use older perl or who want to encode complicated data structures. However 😭 — this may result in a different JSON text from the one JSON::XS encodes (and thus may break tests that compare entire JSON texts). If you do need the previous behavior for compatibility or for finer control, set the PERL_JSON_PP_USE_B environmental variable to true before you use JSON::PP (or JSON.pm). Like, before. Not after. ⭐

Note that numerical precision has the same meaning as under Perl (so binary to decimal conversion follows the same rules as in Perl, which can differ to other languages). Also, your perl interpreter might expose extensions to the floating point numbers of your platform, such as infinities or NaN's — these cannot be represented in JSON, and it is an error to pass those in. 💀

JSON::PP (and JSON::XS) trusts what you pass to the encode method (or the encode_json function) is a clean, validated data structure with values that can be represented as valid JSON values only, because it's not from an external data source (as opposed to JSON texts you pass to decode or decode_json, which JSON::PP considers tainted and doesn't trust). Like, it's giving full main-character trust fall energy 🫶.

Since JSON::PP doesn't know exactly what you and consumers of your JSON texts want the unexpected values to be — you may want to convert them into null, or to stringify them with or without normalisation (string representation of infinities/NaN may vary depending on platforms), or to croak without conversion — you're advised to do what you and your consumers need before you encode, and also not to numify values that may start with values that look like a number (including infinities/NaN), without validating. No cap, just validate first. 🙈

🎀 OBJECT SERIALISATION 🎀

As JSON cannot directly represent Perl objects, you have to choose between a pure JSON representation (without the ability to deserialise the object automatically again), and a nonstandard extension to the JSON syntax, tagged values. Two paths, pick your fighter. ⚔️

✨ SERIALISATION ✨

What happens when JSON::PP encounters a Perl object depends on the allow_blessed, convert_blessed, allow_tags and allow_bignum settings, which are used in this order:

allow_tags is enabled and the object has a FREEZE method. In this case, JSON::PP creates a tagged JSON value, using a nonstandard extension to the JSON syntax.

This works by invoking the FREEZE method on the object, with the first argument being the object to serialise, and the second argument being the constant string JSON to distinguish it from other serialisers.

The FREEZE method can return any number of values (i.e. zero or more). These values and the paclkage/classname of the object will then be encoded as a tagged JSON value in the following format:

("classname")[FREEZE return values...]

e.g.:

("URI")["http://www.google.com/"]
("MyDate")[2013,10,29]
("ImageData::JPEG")["Z3...VlCg=="]

For example, the hypothetical My::Object FREEZE method might use the objects type and id members to encode the object:

sub My::Object::FREEZE {
   my ($self, $serialiser) = @_;

   ($self->{type}, $self->{id})
}

convert_blessed is enabled and the object has a TO_JSON method. In this case, the TO_JSON method of the object is invoked in scalar context. It must return a single scalar that can be directly encoded into JSON. This scalar replaces the object in the JSON text.

For example, the following TO_JSON method will convert all URI objects to JSON strings when serialised. The fact that these values originally were URI objects is lost 😭.

sub URI::TO_JSON {
   my ($uri) = @_;
   $uri->as_string
}

allow_bignum is enabled and the object is a Math::BigInt or Math::BigFloat. The object will be serialised as a JSON number value. 🔢
allow_blessed is enabled. The object will be serialised as a JSON null value.
none of the above If none of the settings are enabled or the respective methods are missing, JSON::PP throws an exception. Bestie it will simply not be chill about it. 💀

🦋 DESERIALISATION 🦋

For deserialisation there are only two cases to consider: either nonstandard tagging was used, in which case allow_tags decides, or objects cannot be automatically be deserialised, in which case you can use postprocessing or the filter_json_object or filter_json_single_key_object callbacks to get some real objects out of your JSON. 🧚

This section only considers the tagged value case: a tagged JSON object is encountered during decoding and allow_tags is disabled, a parse error will result (as if tagged values were not part of the grammar).

If allow_tags is enabled, JSON::PP will look up the THAW method of the package/classname used during serialisation (it will not attempt to load the package as a Perl module). If there is no such method, the decoding will fail with an error. 🙈

Otherwise, the THAW method is invoked with the classname as first argument, the constant string JSON as second argument, and all the values from the JSON array (the values originally returned by the FREEZE method) as remaining arguments.

The method must then return the object. While technically you can return any Perl scalar, you might have to enable the allow_nonref setting to make that work in all cases, so better return an actual blessed reference. Like, do it properly, ok? 👑

As an example, let's implement a THAW function that regenerates the My::Object from the FREEZE example earlier:

sub My::Object::THAW {
   my ($class, $serialiser, $type, $id) = @_;

   $class->new (type => $type, id => $id)
}

💜 ENCODING/CODESET FLAG NOTES 💜

Okay so this whole section is straight-up lifted from JSON::XS, credit where credit is due, and it's genuinely the part everyone gets confused about so bestie please read it.

You've probably seen a bunch of flags floating around that seem to be about encodings or codesets — namely "utf8", "latin1" and "ascii". And there's like, a lot of confusion about what each one actually does, so here's the short comparison:

"utf8" is the one that controls whether the JSON text created by encode (and expected by decode) is UTF-8 encoded or not. Meanwhile "latin1" and "ascii" only control whether encode escapes character values outside their respective codeset range. None of these flags conflict with each other, though ngl some combinations make way less sense than others. 🙈

Care has been taken to make all flags symmetrical with respect to encode and decode — like, texts encoded with any combination of these flag values will be correctly decoded when the same flags are used. So in general: if you use different flag settings while encoding vs. when decoding, you probably have a bug somewhere. 💀

Below is a verbose discussion of these flags. Quick note first: a "codeset" is just an abstract set of character-codepoint pairs, while an encoding takes those codepoint numbers and encodes them — in our case, into octets. Unicode is (among other things) a codeset, UTF-8 is an encoding, and ISO-8859-1 (= latin 1) and ASCII are both codesets and encodings at the same time, which is genuinely so confusing of them. 😭

🌸 `"utf8"` flag disabled

When "utf8" is disabled (that's the default, btw), then encode/decode generate and expect Unicode strings. Meaning: characters with high ordinal Unicode values (> 255) will be encoded as such characters, and likewise such characters are decoded as-is — no changes to them will be done, except "(re-)interpreting" them as Unicode codepoints or Unicode characters, respectively (to Perl these are the same thing in strings unless you do funny/weird/dumb stuff). ✨

This is useful when you want to do the encoding yourself (e.g. when you want to have UTF-16 encoded JSON texts) or when some other layer does the encoding for you. Like, for example, when printing to a terminal using a filehandle that transparently encodes to UTF-8 — in that case you certainly do NOT want to UTF-8 encode your data first and have Perl encode it another time. That's just doing the same job twice and nobody asked. 🙅‍♀️

🦋 `"utf8"` flag enabled

If the "utf8"-flag is enabled, encode/decode will encode all characters using the corresponding UTF-8 multi-byte sequence, and will expect your input strings to be encoded as UTF-8 — that is, no "character" of the input string must have any value > 255, as UTF-8 does not allow that.

So the "utf8" flag basically switches between two modes: disabled means you will get a Unicode string in Perl, enabled means you get an UTF-8 encoded octet/binary string in Perl. Two completely different vibes. 💅

🎀 `"latin1"` or `"ascii"` flags enabled

With "latin1" (or "ascii") enabled, encode will escape characters with ordinal values > 255 (> 127 with "ascii") and encode the remaining characters as specified by the "utf8" flag.

If "utf8" is disabled, then the result is also correctly encoded in those character sets — because both are proper subsets of Unicode, meaning that a Unicode string with all character values < 256 is the same thing as a ISO-8859-1 string, and a Unicode string with all character values < 128 is the same thing as an ASCII string in Perl. Math is mathing. 🧮

If "utf8" is enabled, you still get a correct UTF-8-encoded string, regardless of these flags — just some more characters will be escaped using \uXXXX then before.

⚠️ Heads up: ISO-8859-1-encoded strings are not compatible with UTF-8 encoding, while ASCII-encoded strings are. That's because the ISO-8859-1 encoding is NOT a subset of UTF-8 (despite the ISO-8859-1 codeset being a subset of Unicode), while ASCII is. Lowkey iconic of ASCII honestly.

Surprisingly, decode will ignore these flags and so treat all input values as governed by the "utf8" flag. If it is disabled, this allows you to decode ISO-8859-1- and ASCII-encoded strings, as both strict subsets of Unicode. If it is enabled, you can correctly decode UTF-8 encoded strings.

So neither "latin1" nor "ascii" are incompatible with the "utf8" flag — they only govern when the JSON output engine escapes a character or not.

The main use for "latin1" is to relatively efficiently store binary data as JSON — at the expense of breaking compatibility with most JSON decoders. So like, sure, but know what you're signing up for. 🫶

The main use for "ascii" is to force the output to not contain characters with values > 127, which means you can interpret the resulting string as UTF-8, ISO-8859-1, ASCII, KOI8-R or most about any character set and 8-bit-encoding, and still get the same data structure back. This is useful when your channel for JSON transfer is not 8-bit clean or the encoding might be mangled in between (e.g. in mail), and it works because ASCII is a proper subset of most 8-bit and multibyte encodings in use in the world. It's giving "universally compatible queen". 👑

💀 BUGS 💀

Please report bugs on a specific behavior of this module to RT or GitHub issues (preferred):

https://github.com/makamaka/JSON-PP/issues

https://rt.cpan.org/Public/Dist/Display.html?Queue=JSON-PP

As for new features and requests to change common behaviors — okay so this part is important — please ask the author of JSON::XS (Marc Lehmann, <schmorp[at]schmorp.de>) first, by email (important!), to keep compatibility among JSON.pm backends. Do not skip this step, bestie, it's there for a reason. 📧

Generally speaking, if you need something special for you, you are advised to create a new module — maybe based on JSON::Tiny, which is smaller and written in a much cleaner way than this module. Sometimes the answer really is "make your own". 🧚

🌈 SEE ALSO 🌈

The json_pp command line utility for quick experiments. Perfect for when you just wanna poke at something real fast.
JSON::XS, Cpanel::JSON::XS, and JSON::Tiny for faster alternatives. Speed queens. 🔥
JSON and JSON::MaybeXS for easy migration.
JSON::backportPP::Compat5005 and JSON::backportPP::Compat5006 for older perl users. We love inclusivity. 💜
RFC4627 (http://www.ietf.org/rfc/rfc4627.txt)
RFC7159 (http://www.ietf.org/rfc/rfc7159.txt)
RFC8259 (http://www.ietf.org/rfc/rfc8259.txt)

✨ AUTHOR ✨

Makamaka Hannyaharamitu, <makamaka[at]cpan.org>

👑 CURRENT MAINTAINER 👑

Kenichi Ishigaki, <ishigaki[at]cpan.org>

🎀 COPYRIGHT AND LICENSE 🎀

Most of the documentation is taken from JSON::XS by Marc Lehmann

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

and that's the whole page, bestie!! 🫶💖✨ This edition comes from perl v5.42.0, dated 2022-10-10 — so go forth, encode responsibly, and remember: same flags on both sides or it's a bug. mwah 💅🌸

📦 where this page comes from

opensuse-leap 16.0: perl-JSON 4.10-160000.2.2 · Artistic-1.0 OR GPL-1.0-or-later
💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on 2026-11-06: a language model's rewrite of the original, under its terms

JSON::backportPP(3)

💖 JSON::backportPP(3) 💖

✨ NAME ✨

✨ SYNOPSIS ✨

✨ DESCRIPTION ✨

✨ FUNCTIONAL INTERFACE ✨

🎀 encode_json

🎀 decode_json

🎀 JSON::PP::is_bool

✨ OBJECT-ORIENTED INTERFACE ✨

🦋 new

🦋 ascii

🦋 latin1

🦋 utf8

🦋 pretty

🦋 indent

🦋 space_before

🦋 space_after

🦋 relaxed

canonical 🎀

allow_nonref 🌈

allow_unknown 🫶

allow_blessed 💜

convert_blessed 🦋

allow_tags 🍓

boolean_values ⭐

core_bools 🔥

filter_json_object 🌸

filter_json_single_key_object 🧚

shrink 🦋

max_depth 🎀

🌸 max_size 🌸

💖 encode 💖

💜 decode 💜

🦋 decode_prefix 🦋

✨ FLAGS FOR JSON::PP ONLY ✨

🎀 allow_singlequote 🎀

🌸 allow_barekey 🌸

💜 allow_bignum 💜

🦋 loose 🦋

💖 escape_slash 💖

🌈 indent_length 🌈

🍓 sort_by 🍓

✨ INCREMENTAL PARSING ✨

💅 incr_parse 💅

🎀 incr_text 🎀

🦋 incr_skip 🦋

🌈 incr_reset 🌈

🗺️ MAPPING 🗺️

🔁 JSON -> PERL 🔁

🌸 object 🌸

🍓 array 🍓

🧚 string 🧚

🔥 number 🔥

✅ true, false ✅

🫧 null 🫧

💬 shell-style comments (# text) 💬

🏷️ tagged values ((tag)value) 🏷️

🪄 PERL -> JSON 🪄

👑 hash references 👑

🌟 array references 🌟

🌀 other references 🌀

💖 JSON::PP::true, JSON::PP::false 💖

🌙 JSON::PP::null 🌙

🎁 blessed objects 🎁

🧸 simple scalars 🧸

🎀 OBJECT SERIALISATION 🎀

✨ SERIALISATION ✨

🦋 DESERIALISATION 🦋

💜 ENCODING/CODESET FLAG NOTES 💜

🌸 "utf8" flag disabled

🦋 "utf8" flag enabled

🎀 "latin1" or "ascii" flags enabled

💀 BUGS 💀

🌈 SEE ALSO 🌈

✨ AUTHOR ✨

👑 CURRENT MAINTAINER 👑

🎀 COPYRIGHT AND LICENSE 🎀

💬 shell-style comments (`# text`) 💬

🏷️ tagged values (`(tag)value`) 🏷️

💖 `JSON::PP::true`, `JSON::PP::false` 💖

🌙 `JSON::PP::null` 🌙

🌸 `"utf8"` flag disabled

🦋 `"utf8"` flag enabled

🎀 `"latin1"` or `"ascii"` flags enabled