Profile of (eval 12)[JSON.pm:268]

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NYTProf Performance Profile
For t/app_dpath.t
Run on Tue Jun 5 15:25:28 2012
Reported on Tue Jun 5 15:26:10 2012

Filename | (eval 12)[/home/ss5/perl5/perlbrew/perls/perl-5.14.1/lib/site_perl/5.14.1/JSON.pm:268]
Statements | Executed 20 statements in 4.94ms
Eval Invoked At | /home/ss5/perl5/perlbrew/perls/perl-5.14.1/lib/site_perl/5.14.1/JSON.pm line 268

Subroutines
Calls | P | F | Exclusive Time | Inclusive Time | Subroutine
--- | --- | --- | --- | --- | ---
1 | 1 | 1 | 4.76ms | 6.27ms | JSON::Backend::XS::::BEGIN@9 JSON::Backend::XS::BEGIN@9
1 | 1 | 1 | 102µs | 102µs | JSON::Backend::XS::::init JSON::Backend::XS::init
1 | 1 | 1 | 39µs | 91µs | JSON::Backend::XS::Supportable::::BEGIN@99JSON::Backend::XS::Supportable::BEGIN@99
1 | 1 | 1 | 37µs | 155µs | JSON::Backend::XS::::BEGIN@11 JSON::Backend::XS::BEGIN@11
1 | 1 | 1 | 30µs | 139µs | JSON::Backend::XS::::BEGIN@18 JSON::Backend::XS::BEGIN@18
1 | 1 | 1 | 28µs | 80µs | JSON::Backend::XS::::BEGIN@29 JSON::Backend::XS::BEGIN@29
1 | 1 | 1 | 26µs | 64µs | JSON::Backend::XS::::BEGIN@42 JSON::Backend::XS::BEGIN@42
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::__ANON__[:110]JSON::Backend::XS::Supportable::__ANON__[:110]
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::__ANON__[:114]JSON::Backend::XS::Supportable::__ANON__[:114]
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::_decodeJSON::Backend::XS::Supportable::_decode
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::_encodeJSON::Backend::XS::Supportable::_encode
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::_incr_parseJSON::Backend::XS::Supportable::_incr_parse
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::_make_unsupported_methodJSON::Backend::XS::Supportable::_make_unsupported_method
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::_set_for_ppJSON::Backend::XS::Supportable::_set_for_pp
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::decode_prefixJSON::Backend::XS::Supportable::decode_prefix
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::get_indent_lengthJSON::Backend::XS::Supportable::get_indent_length
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::Supportable::::indent_lengthJSON::Backend::XS::Supportable::indent_length
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::::__ANON__[:32] JSON::Backend::XS::__ANON__[:32]
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::::__ANON__[:33] JSON::Backend::XS::__ANON__[:33]
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::::__ANON__[:63] JSON::Backend::XS::__ANON__[:63]
0 | 0 | 0 | 0s | 0s | JSON::Backend::XS::::support_by_pp JSON::Backend::XS::support_by_pp

Call graph for these subroutines as a Graphviz dot language file.

Line | State ments | Time on line | Calls | Time in subs | Code
--- | --- | --- | --- | --- | ---
1 |  |  |  |  |
2 |  |  |  |  |
3 |  |  |  |  | #
4 |  |  |  |  | # Helper classes for Backend Module (XS)
5 |  |  |  |  | #
6 |  |  |  |  |
7 |  |  |  |  | package JSON::Backend::XS;
8 |  |  |  |  |
9 | 2 | 537µs | 2 | 6.58ms | # spent 6.27ms (4.76+1.51) within JSON::Backend::XS::BEGIN@9 which was called: # once (4.76ms+1.51ms) by JSON::_load_xs at line 9 use constant INDENT_LENGTH_FLAG => 15 << 12; # spent 6.27ms making 1 call to JSON::Backend::XS::BEGIN@9 # spent 306µs making 1 call to constant::import
10 |  |  |  |  |
11 | 1 | 25µs | 1 | 118µs | # spent 155µs (37+118) within JSON::Backend::XS::BEGIN@11 which was called: # once (37µs+118µs) by JSON::_load_xs at line 16 use constant UNSUPPORTED_ENCODE_FLAG => { # spent 118µs making 1 call to constant::import
12 |  |  |  |  | ESCAPE_SLASH => 0x00000010,
13 |  |  |  |  | ALLOW_BIGNUM => 0x00000020,
14 |  |  |  |  | AS_NONBLESSED => 0x00000040,
15 |  |  |  |  | EXPANDED => 0x10000000, # for developer's
16 | 1 | 103µs | 1 | 155µs | }; # spent 155µs making 1 call to JSON::Backend::XS::BEGIN@11
17 |  |  |  |  |
18 | 1 | 23µs | 1 | 108µs | # spent 139µs (30+109) within JSON::Backend::XS::BEGIN@18 which was called: # once (30µs+109µs) by JSON::_load_xs at line 24 use constant UNSUPPORTED_DECODE_FLAG => { # spent 108µs making 1 call to constant::import
19 |  |  |  |  | LOOSE => 0x00000001,
20 |  |  |  |  | ALLOW_BIGNUM => 0x00000002,
21 |  |  |  |  | ALLOW_BAREKEY => 0x00000004,
22 |  |  |  |  | ALLOW_SINGLEQUOTE => 0x00000008,
23 |  |  |  |  | EXPANDED => 0x20000000, # for developer's
24 | 1 | 207µs | 1 | 139µs | }; # spent 139µs making 1 call to JSON::Backend::XS::BEGIN@18
25 |  |  |  |  |
26 |  |  |  |  |
27 |  |  |  |  | # spent 102µs within JSON::Backend::XS::init which was called: # once (102µs+0s) by JSON::_load_xs at line 269 of JSON.pm sub init {
28 | 1 | 9µs |  |  | local $^W;
29 | 2 | 485µs | 2 | 131µs | # spent 80µs (28+52) within JSON::Backend::XS::BEGIN@29 which was called: # once (28µs+52µs) by JSON::_load_xs at line 29 no strict qw(refs); # spent 80µs making 1 call to JSON::Backend::XS::BEGIN@29 # spent 51µs making 1 call to strict::unimport
30 | 1 | 15µs |  |  | *{"JSON::decode_json"} = \&{"JSON::XS::decode_json"};
31 | 1 | 8µs |  |  | *{"JSON::encode_json"} = \&{"JSON::XS::encode_json"};
32 | 1 | 22µs |  |  | *{"JSON::XS::is_xs"} = sub { 1 };
33 | 1 | 32µs |  |  | *{"JSON::XS::is_pp"} = sub { 0 };
34 | 1 | 27µs |  |  | return 1;
35 |  |  |  |  | }
36 |  |  |  |  |
37 |  |  |  |  |
38 |  |  |  |  | sub support_by_pp {
39 |  |  |  |  | my ($class, @methods) = @_;
40 |  |  |  |  |
41 |  |  |  |  | local $^W;
42 | 2 | 1.22ms | 2 | 101µs | # spent 64µs (26+37) within JSON::Backend::XS::BEGIN@42 which was called: # once (26µs+37µs) by JSON::_load_xs at line 42 no strict qw(refs); # spent 64µs making 1 call to JSON::Backend::XS::BEGIN@42 # spent 38µs making 1 call to strict::unimport
43 |  |  |  |  |
44 |  |  |  |  | my $JSON_XS_encode_orignal = \&JSON::XS::encode;
45 |  |  |  |  | my $JSON_XS_decode_orignal = \&JSON::XS::decode;
46 |  |  |  |  | my $JSON_XS_incr_parse_orignal = \&JSON::XS::incr_parse;
47 |  |  |  |  |
48 |  |  |  |  | *JSON::XS::decode = \&JSON::Backend::XS::Supportable::_decode;
49 |  |  |  |  | *JSON::XS::encode = \&JSON::Backend::XS::Supportable::_encode;
50 |  |  |  |  | *JSON::XS::incr_parse = \&JSON::Backend::XS::Supportable::_incr_parse;
51 |  |  |  |  |
52 |  |  |  |  | *{JSON::XS::_original_decode} = $JSON_XS_decode_orignal;
53 |  |  |  |  | *{JSON::XS::_original_encode} = $JSON_XS_encode_orignal;
54 |  |  |  |  | *{JSON::XS::_original_incr_parse} = $JSON_XS_incr_parse_orignal;
55 |  |  |  |  |
56 |  |  |  |  | push @JSON::Backend::XS::Supportable::ISA, 'JSON';
57 |  |  |  |  |
58 |  |  |  |  | my $pkg = 'JSON::Backend::XS::Supportable';
59 |  |  |  |  |
60 |  |  |  |  | *{JSON::new} = sub {
61 |  |  |  |  | my $proto = new JSON::XS; $$proto = 0;
62 |  |  |  |  | bless $proto, $pkg;
63 |  |  |  |  | };
64 |  |  |  |  |
65 |  |  |  |  |
66 |  |  |  |  | for my $method (@methods) {
67 |  |  |  |  | my $flag = uc($method);
68 |  |  |  |  | my $type |= (UNSUPPORTED_ENCODE_FLAG->{$flag} || 0);
69 |  |  |  |  | $type |= (UNSUPPORTED_DECODE_FLAG->{$flag} || 0);
70 |  |  |  |  |
71 |  |  |  |  | next unless($type);
72 |  |  |  |  |
73 |  |  |  |  | $pkg->_make_unsupported_method($method => $type);
74 |  |  |  |  | }
75 |  |  |  |  |
76 |  |  |  |  | push @{"JSON::XS::Boolean::ISA"}, qw(JSON::PP::Boolean);
77 |  |  |  |  | push @{"JSON::PP::Boolean::ISA"}, qw(JSON::Boolean);
78 |  |  |  |  |
79 |  |  |  |  | $JSON::DEBUG and Carp::carp("set -support_by_pp mode.");
80 |  |  |  |  |
81 |  |  |  |  | return 1;
82 |  |  |  |  | }
83 |  |  |  |  |
- - |  |  |  |  |
87 |  |  |  |  | #
88 |  |  |  |  | # Helper classes for XS
89 |  |  |  |  | #
90 |  |  |  |  |
91 |  |  |  |  | package JSON::Backend::XS::Supportable;
92 |  |  |  |  |
93 | 1 | 4µs |  |  | $Carp::Internal{'JSON::Backend::XS::Supportable'} = 1;
94 |  |  |  |  |
95 |  |  |  |  | sub _make_unsupported_method {
96 |  |  |  |  | my ($pkg, $method, $type) = @_;
97 |  |  |  |  |
98 |  |  |  |  | local $^W;
99 | 2 | 2.21ms | 2 | 143µs | # spent 91µs (39+52) within JSON::Backend::XS::Supportable::BEGIN@99 which was called: # once (39µs+52µs) by JSON::_load_xs at line 99 no strict qw(refs); # spent 91µs making 1 call to JSON::Backend::XS::Supportable::BEGIN@99 # spent 52µs making 1 call to strict::unimport
100 |  |  |  |  |
101 |  |  |  |  | *{"$pkg\::$method"} = sub {
102 |  |  |  |  | local $^W;
103 |  |  |  |  | if (defined $_[1] ? $_[1] : 1) {
104 |  |  |  |  | ${$_[0]} |= $type;
105 |  |  |  |  | }
106 |  |  |  |  | else {
107 |  |  |  |  | ${$_[0]} &= ~$type;
108 |  |  |  |  | }
109 |  |  |  |  | $_[0];
110 |  |  |  |  | };
111 |  |  |  |  |
112 |  |  |  |  | *{"$pkg\::get_$method"} = sub {
113 |  |  |  |  | ${$_[0]} & $type ? 1 : '';
114 |  |  |  |  | };
115 |  |  |  |  |
116 |  |  |  |  | }
117 |  |  |  |  |
118 |  |  |  |  |
119 |  |  |  |  | sub _set_for_pp {
120 |  |  |  |  | JSON::_load_pp( $_INSTALL_ONLY );
121 |  |  |  |  |
122 |  |  |  |  | my $type = shift;
123 |  |  |  |  | my $pp = new JSON::PP;
124 |  |  |  |  | my $prop = $_[0]->property;
125 |  |  |  |  |
126 |  |  |  |  | for my $name (keys %$prop) {
127 |  |  |  |  | $pp->$name( $prop->{$name} ? $prop->{$name} : 0 );
128 |  |  |  |  | }
129 |  |  |  |  |
130 |  |  |  |  | my $unsupported = $type eq 'encode' ? JSON::Backend::XS::UNSUPPORTED_ENCODE_FLAG
131 |  |  |  |  | : JSON::Backend::XS::UNSUPPORTED_DECODE_FLAG;
132 |  |  |  |  | my $flags = ${$_[0]} || 0;
133 |  |  |  |  |
134 |  |  |  |  | for my $name (keys %$unsupported) {
135 |  |  |  |  | next if ($name eq 'EXPANDED'); # for developer's
136 |  |  |  |  | my $enable = ($flags & $unsupported->{$name}) ? 1 : 0;
137 |  |  |  |  | my $method = lc $name;
138 |  |  |  |  | $pp->$method($enable);
139 |  |  |  |  | }
140 |  |  |  |  |
141 |  |  |  |  | $pp->indent_length( $_[0]->get_indent_length );
142 |  |  |  |  |
143 |  |  |  |  | return $pp;
144 |  |  |  |  | }
145 |  |  |  |  |
146 |  |  |  |  | sub _encode { # using with PP encod
147 |  |  |  |  | if (${$_[0]}) {
148 |  |  |  |  | _set_for_pp('encode' => @_)->encode($_[1]);
149 |  |  |  |  | }
150 |  |  |  |  | else {
151 |  |  |  |  | $_[0]->_original_encode( $_[1] );
152 |  |  |  |  | }
153 |  |  |  |  | }
154 |  |  |  |  |
155 |  |  |  |  |
156 |  |  |  |  | sub _decode { # if unsupported-flag is set, use PP
157 |  |  |  |  | if (${$_[0]}) {
158 |  |  |  |  | _set_for_pp('decode' => @_)->decode($_[1]);
159 |  |  |  |  | }
160 |  |  |  |  | else {
161 |  |  |  |  | $_[0]->_original_decode( $_[1] );
162 |  |  |  |  | }
163 |  |  |  |  | }
164 |  |  |  |  |
165 |  |  |  |  |
166 |  |  |  |  | sub decode_prefix { # if unsupported-flag is set, use PP
167 |  |  |  |  | _set_for_pp('decode' => @_)->decode_prefix($_[1]);
168 |  |  |  |  | }
169 |  |  |  |  |
170 |  |  |  |  |
171 |  |  |  |  | sub _incr_parse {
172 |  |  |  |  | if (${$_[0]}) {
173 |  |  |  |  | _set_for_pp('decode' => @_)->incr_parse($_[1]);
174 |  |  |  |  | }
175 |  |  |  |  | else {
176 |  |  |  |  | $_[0]->_original_incr_parse( $_[1] );
177 |  |  |  |  | }
178 |  |  |  |  | }
179 |  |  |  |  |
180 |  |  |  |  |
181 |  |  |  |  | sub get_indent_length {
182 |  |  |  |  | ${$_[0]} << 4 >> 16;
183 |  |  |  |  | }
184 |  |  |  |  |
185 |  |  |  |  |
186 |  |  |  |  | sub indent_length {
187 |  |  |  |  | my $length = $_[1];
188 |  |  |  |  |
189 |  |  |  |  | if (!defined $length or $length > 15 or $length < 0) {
190 |  |  |  |  | Carp::carp "The acceptable range of indent_length() is 0 to 15.";
191 |  |  |  |  | }
192 |  |  |  |  | else {
193 |  |  |  |  | local $^W;
194 |  |  |  |  | $length <<= 12;
195 |  |  |  |  | ${$_[0]} &= ~ JSON::Backend::XS::INDENT_LENGTH_FLAG;
196 |  |  |  |  | ${$_[0]} |= $length;
197 |  |  |  |  | *JSON::XS::encode = \&JSON::Backend::XS::Supportable::_encode;
198 |  |  |  |  | }
199 |  |  |  |  |
200 |  |  |  |  | $_[0];
201 |  |  |  |  | }
202 |  |  |  |  |
203 |  |  |  |  |
204 | 1 | 12µs |  |  | 1;
205 |  |  |  |  | __END__
206 |  |  |  |  |
207 |  |  |  |  | =head1 NAME
208 |  |  |  |  |
209 |  |  |  |  | JSON - JSON (JavaScript Object Notation) encoder/decoder
210 |  |  |  |  |
211 |  |  |  |  | =head1 SYNOPSIS
212 |  |  |  |  |
213 |  |  |  |  | use JSON; # imports encode_json, decode_json, to_json and from_json.
214 |  |  |  |  |
215 |  |  |  |  | # simple and fast interfaces (expect/generate UTF-8)
216 |  |  |  |  |
217 |  |  |  |  | $utf8_encoded_json_text = encode_json $perl_hash_or_arrayref;
218 |  |  |  |  | $perl_hash_or_arrayref = decode_json $utf8_encoded_json_text;
219 |  |  |  |  |
220 |  |  |  |  | # OO-interface
221 |  |  |  |  |
222 |  |  |  |  | $json = JSON->new->allow_nonref;
223 |  |  |  |  |
224 |  |  |  |  | $json_text = $json->encode( $perl_scalar );
225 |  |  |  |  | $perl_scalar = $json->decode( $json_text );
226 |  |  |  |  |
227 |  |  |  |  | $pretty_printed = $json->pretty->encode( $perl_scalar ); # pretty-printing
228 |  |  |  |  |
229 |  |  |  |  | # If you want to use PP only support features, call with '-support_by_pp'
230 |  |  |  |  | # When XS unsupported feature is enable, using PP (de|en)code instead of XS ones.
231 |  |  |  |  |
232 |  |  |  |  | use JSON -support_by_pp;
233 |  |  |  |  |
234 |  |  |  |  | # option-acceptable interfaces (expect/generate UNICODE by default)
235 |  |  |  |  |
236 |  |  |  |  | $json_text = to_json( $perl_scalar, { ascii => 1, pretty => 1 } );
237 |  |  |  |  | $perl_scalar = from_json( $json_text, { utf8 => 1 } );
238 |  |  |  |  |
239 |  |  |  |  | # Between (en|de)code_json and (to|from)_json, if you want to write
240 |  |  |  |  | # a code which communicates to an outer world (encoded in UTF-8),
241 |  |  |  |  | # recommend to use (en|de)code_json.
242 |  |  |  |  |
243 |  |  |  |  | =head1 VERSION
244 |  |  |  |  |
245 |  |  |  |  | 2.53
246 |  |  |  |  |
247 |  |  |  |  | This version is compatible with JSON::XS B<2.27> and later.
248 |  |  |  |  |
249 |  |  |  |  |
250 |  |  |  |  | =head1 NOTE
251 |  |  |  |  |
252 |  |  |  |  | JSON::PP was inculded in C<JSON> distribution.
253 |  |  |  |  | It comes to be a perl core module in Perl 5.14.
254 |  |  |  |  | And L<JSON::PP> will be split away it.
255 |  |  |  |  |
256 |  |  |  |  | C<JSON> distribution will inculde yet another JSON::PP modules.
257 |  |  |  |  | They are JSNO::backportPP and so on. JSON.pm should work as it did at all.
258 |  |  |  |  |
259 |  |  |  |  | =head1 DESCRIPTION
260 |  |  |  |  |
261 |  |  |  |  | ************************** CAUTION ********************************
262 |  |  |  |  | * This is 'JSON module version 2' and there are many differences *
263 |  |  |  |  | * to version 1.xx *
264 |  |  |  |  | * Please check your applications useing old version. *
265 |  |  |  |  | * See to 'INCOMPATIBLE CHANGES TO OLD VERSION' *
266 |  |  |  |  | *******************************************************************
267 |  |  |  |  |
268 |  |  |  |  | JSON (JavaScript Object Notation) is a simple data format.
269 |  |  |  |  | See to L<http://www.json.org/> and C<RFC4627>(L<http://www.ietf.org/rfc/rfc4627.txt>).
270 |  |  |  |  |
271 |  |  |  |  | This module converts Perl data structures to JSON and vice versa using either
272 |  |  |  |  | L<JSON::XS> or L<JSON::PP>.
273 |  |  |  |  |
274 |  |  |  |  | JSON::XS is the fastest and most proper JSON module on CPAN which must be
275 |  |  |  |  | compiled and installed in your environment.
276 |  |  |  |  | JSON::PP is a pure-Perl module which is bundled in this distribution and
277 |  |  |  |  | has a strong compatibility to JSON::XS.
278 |  |  |  |  |
279 |  |  |  |  | This module try to use JSON::XS by default and fail to it, use JSON::PP instead.
280 |  |  |  |  | So its features completely depend on JSON::XS or JSON::PP.
281 |  |  |  |  |
282 |  |  |  |  | See to L<BACKEND MODULE DECISION>.
283 |  |  |  |  |
284 |  |  |  |  | To distinguish the module name 'JSON' and the format type JSON,
285 |  |  |  |  | the former is quoted by CE<lt>E<gt> (its results vary with your using media),
286 |  |  |  |  | and the latter is left just as it is.
287 |  |  |  |  |
288 |  |  |  |  | Module name : C<JSON>
289 |  |  |  |  |
290 |  |  |  |  | Format type : JSON
291 |  |  |  |  |
292 |  |  |  |  | =head2 FEATURES
293 |  |  |  |  |
294 |  |  |  |  | =over
295 |  |  |  |  |
296 |  |  |  |  | =item * correct unicode handling
297 |  |  |  |  |
298 |  |  |  |  | This module (i.e. backend modules) knows how to handle Unicode, documents
299 |  |  |  |  | how and when it does so, and even documents what "correct" means.
300 |  |  |  |  |
301 |  |  |  |  | Even though there are limitations, this feature is available since Perl version 5.6.
302 |  |  |  |  |
303 |  |  |  |  | JSON::XS requires Perl 5.8.2 (but works correctly in 5.8.8 or later), so in older versions
304 |  |  |  |  | C<JSON> sholud call JSON::PP as the backend which can be used since Perl 5.005.
305 |  |  |  |  |
306 |  |  |  |  | With Perl 5.8.x JSON::PP works, but from 5.8.0 to 5.8.2, because of a Perl side problem,
307 |  |  |  |  | JSON::PP works slower in the versions. And in 5.005, the Unicode handling is not available.
308 |  |  |  |  | See to L<JSON::PP/UNICODE HANDLING ON PERLS> for more information.
309 |  |  |  |  |
310 |  |  |  |  | See also to L<JSON::XS/A FEW NOTES ON UNICODE AND PERL>
311 |  |  |  |  | and L<JSON::XS/ENCODING/CODESET_FLAG_NOTES>.
312 |  |  |  |  |
313 |  |  |  |  |
314 |  |  |  |  | =item * round-trip integrity
315 |  |  |  |  |
316 |  |  |  |  | When you serialise a perl data structure using only data types supported
317 |  |  |  |  | by JSON and Perl, the deserialised data structure is identical on the Perl
318 |  |  |  |  | level. (e.g. the string "2.0" doesn't suddenly become "2" just because
319 |  |  |  |  | it looks like a number). There I<are> minor exceptions to this, read the
320 |  |  |  |  | L</MAPPING> section below to learn about those.
321 |  |  |  |  |
322 |  |  |  |  |
323 |  |  |  |  | =item * strict checking of JSON correctness
324 |  |  |  |  |
325 |  |  |  |  | There is no guessing, no generating of illegal JSON texts by default,
326 |  |  |  |  | and only JSON is accepted as input by default (the latter is a security
327 |  |  |  |  | feature).
328 |  |  |  |  |
329 |  |  |  |  | See to L<JSON::XS/FEATURES> and L<JSON::PP/FEATURES>.
330 |  |  |  |  |
331 |  |  |  |  | =item * fast
332 |  |  |  |  |
333 |  |  |  |  | This module returns a JSON::XS object itself if available.
334 |  |  |  |  | Compared to other JSON modules and other serialisers such as Storable,
335 |  |  |  |  | JSON::XS usually compares favourably in terms of speed, too.
336 |  |  |  |  |
337 |  |  |  |  | If not available, C<JSON> returns a JSON::PP object instead of JSON::XS and
338 |  |  |  |  | it is very slow as pure-Perl.
339 |  |  |  |  |
340 |  |  |  |  | =item * simple to use
341 |  |  |  |  |
342 |  |  |  |  | This module has both a simple functional interface as well as an
343 |  |  |  |  | object oriented interface interface.
344 |  |  |  |  |
345 |  |  |  |  | =item * reasonably versatile output formats
346 |  |  |  |  |
347 |  |  |  |  | You can choose between the most compact guaranteed-single-line format possible
348 |  |  |  |  | (nice for simple line-based protocols), a pure-ASCII format (for when your transport
349 |  |  |  |  | is not 8-bit clean, still supports the whole Unicode range), or a pretty-printed
350 |  |  |  |  | format (for when you want to read that stuff). Or you can combine those features
351 |  |  |  |  | in whatever way you like.
352 |  |  |  |  |
353 |  |  |  |  | =back
354 |  |  |  |  |
355 |  |  |  |  | =head1 FUNCTIONAL INTERFACE
356 |  |  |  |  |
357 |  |  |  |  | Some documents are copied and modified from L<JSON::XS/FUNCTIONAL INTERFACE>.
358 |  |  |  |  | C<to_json> and C<from_json> are additional functions.
359 |  |  |  |  |
360 |  |  |  |  | =head2 encode_json
361 |  |  |  |  |
362 |  |  |  |  | $json_text = encode_json $perl_scalar
363 |  |  |  |  |
364 |  |  |  |  | Converts the given Perl data structure to a UTF-8 encoded, binary string.
365 |  |  |  |  |
366 |  |  |  |  | This function call is functionally identical to:
367 |  |  |  |  |
368 |  |  |  |  | $json_text = JSON->new->utf8->encode($perl_scalar)
369 |  |  |  |  |
370 |  |  |  |  | =head2 decode_json
371 |  |  |  |  |
372 |  |  |  |  | $perl_scalar = decode_json $json_text
373 |  |  |  |  |
374 |  |  |  |  | The opposite of C<encode_json>: expects an UTF-8 (binary) string and tries
375 |  |  |  |  | to parse that as an UTF-8 encoded JSON text, returning the resulting
376 |  |  |  |  | reference.
377 |  |  |  |  |
378 |  |  |  |  | This function call is functionally identical to:
379 |  |  |  |  |
380 |  |  |  |  | $perl_scalar = JSON->new->utf8->decode($json_text)
381 |  |  |  |  |
382 |  |  |  |  |
383 |  |  |  |  | =head2 to_json
384 |  |  |  |  |
385 |  |  |  |  | $json_text = to_json($perl_scalar)
386 |  |  |  |  |
387 |  |  |  |  | Converts the given Perl data structure to a json string.
388 |  |  |  |  |
389 |  |  |  |  | This function call is functionally identical to:
390 |  |  |  |  |
391 |  |  |  |  | $json_text = JSON->new->encode($perl_scalar)
392 |  |  |  |  |
393 |  |  |  |  | Takes a hash reference as the second.
394 |  |  |  |  |
395 |  |  |  |  | $json_text = to_json($perl_scalar, $flag_hashref)
396 |  |  |  |  |
397 |  |  |  |  | So,
398 |  |  |  |  |
399 |  |  |  |  | $json_text = to_json($perl_scalar, {utf8 => 1, pretty => 1})
400 |  |  |  |  |
401 |  |  |  |  | equivalent to:
402 |  |  |  |  |
403 |  |  |  |  | $json_text = JSON->new->utf8(1)->pretty(1)->encode($perl_scalar)
404 |  |  |  |  |
405 |  |  |  |  | If you want to write a modern perl code which communicates to outer world,
406 |  |  |  |  | you should use C<encode_json> (supposed that JSON data are encoded in UTF-8).
407 |  |  |  |  |
408 |  |  |  |  | =head2 from_json
409 |  |  |  |  |
410 |  |  |  |  | $perl_scalar = from_json($json_text)
411 |  |  |  |  |
412 |  |  |  |  | The opposite of C<to_json>: expects a json string and tries
413 |  |  |  |  | to parse it, returning the resulting reference.
414 |  |  |  |  |
415 |  |  |  |  | This function call is functionally identical to:
416 |  |  |  |  |
417 |  |  |  |  | $perl_scalar = JSON->decode($json_text)
418 |  |  |  |  |
419 |  |  |  |  | Takes a hash reference as the second.
420 |  |  |  |  |
421 |  |  |  |  | $perl_scalar = from_json($json_text, $flag_hashref)
422 |  |  |  |  |
423 |  |  |  |  | So,
424 |  |  |  |  |
425 |  |  |  |  | $perl_scalar = from_json($json_text, {utf8 => 1})
426 |  |  |  |  |
427 |  |  |  |  | equivalent to:
428 |  |  |  |  |
429 |  |  |  |  | $perl_scalar = JSON->new->utf8(1)->decode($json_text)
430 |  |  |  |  |
431 |  |  |  |  | If you want to write a modern perl code which communicates to outer world,
432 |  |  |  |  | you should use C<decode_json> (supposed that JSON data are encoded in UTF-8).
433 |  |  |  |  |
434 |  |  |  |  | =head2 JSON::is_bool
435 |  |  |  |  |
436 |  |  |  |  | $is_boolean = JSON::is_bool($scalar)
437 |  |  |  |  |
438 |  |  |  |  | Returns true if the passed scalar represents either JSON::true or
439 |  |  |  |  | JSON::false, two constants that act like C<1> and C<0> respectively
440 |  |  |  |  | and are also used to represent JSON C<true> and C<false> in Perl strings.
441 |  |  |  |  |
442 |  |  |  |  | =head2 JSON::true
443 |  |  |  |  |
444 |  |  |  |  | Returns JSON true value which is blessed object.
445 |  |  |  |  | It C<isa> JSON::Boolean object.
446 |  |  |  |  |
447 |  |  |  |  | =head2 JSON::false
448 |  |  |  |  |
449 |  |  |  |  | Returns JSON false value which is blessed object.
450 |  |  |  |  | It C<isa> JSON::Boolean object.
451 |  |  |  |  |
452 |  |  |  |  | =head2 JSON::null
453 |  |  |  |  |
454 |  |  |  |  | Returns C<undef>.
455 |  |  |  |  |
456 |  |  |  |  | See L<MAPPING>, below, for more information on how JSON values are mapped to
457 |  |  |  |  | Perl.
458 |  |  |  |  |
459 |  |  |  |  | =head1 HOW DO I DECODE A DATA FROM OUTER AND ENCODE TO OUTER
460 |  |  |  |  |
461 |  |  |  |  | This section supposes that your perl vresion is 5.8 or later.
462 |  |  |  |  |
463 |  |  |  |  | If you know a JSON text from an outer world - a network, a file content, and so on,
464 |  |  |  |  | is encoded in UTF-8, you should use C<decode_json> or C<JSON> module object
465 |  |  |  |  | with C<utf8> enable. And the decoded result will contain UNICODE characters.
466 |  |  |  |  |
467 |  |  |  |  | # from network
468 |  |  |  |  | my $json = JSON->new->utf8;
469 |  |  |  |  | my $json_text = CGI->new->param( 'json_data' );
470 |  |  |  |  | my $perl_scalar = $json->decode( $json_text );
471 |  |  |  |  |
472 |  |  |  |  | # from file content
473 |  |  |  |  | local $/;
474 |  |  |  |  | open( my $fh, '<', 'json.data' );
475 |  |  |  |  | $json_text = <$fh>;
476 |  |  |  |  | $perl_scalar = decode_json( $json_text );
477 |  |  |  |  |
478 |  |  |  |  | If an outer data is not encoded in UTF-8, firstly you should C<decode> it.
479 |  |  |  |  |
480 |  |  |  |  | use Encode;
481 |  |  |  |  | local $/;
482 |  |  |  |  | open( my $fh, '<', 'json.data' );
483 |  |  |  |  | my $encoding = 'cp932';
484 |  |  |  |  | my $unicode_json_text = decode( $encoding, <$fh> ); # UNICODE
485 |  |  |  |  |
486 |  |  |  |  | # or you can write the below code.
487 |  |  |  |  | #
488 |  |  |  |  | # open( my $fh, "<:encoding($encoding)", 'json.data' );
489 |  |  |  |  | # $unicode_json_text = <$fh>;
490 |  |  |  |  |
491 |  |  |  |  | In this case, C<$unicode_json_text> is of course UNICODE string.
492 |  |  |  |  | So you B<cannot> use C<decode_json> nor C<JSON> module object with C<utf8> enable.
493 |  |  |  |  | Instead of them, you use C<JSON> module object with C<utf8> disable or C<from_json>.
494 |  |  |  |  |
495 |  |  |  |  | $perl_scalar = $json->utf8(0)->decode( $unicode_json_text );
496 |  |  |  |  | # or
497 |  |  |  |  | $perl_scalar = from_json( $unicode_json_text );
498 |  |  |  |  |
499 |  |  |  |  | Or C<encode 'utf8'> and C<decode_json>:
500 |  |  |  |  |
501 |  |  |  |  | $perl_scalar = decode_json( encode( 'utf8', $unicode_json_text ) );
502 |  |  |  |  | # this way is not efficient.
503 |  |  |  |  |
504 |  |  |  |  | And now, you want to convert your C<$perl_scalar> into JSON data and
505 |  |  |  |  | send it to an outer world - a network or a file content, and so on.
506 |  |  |  |  |
507 |  |  |  |  | Your data usually contains UNICODE strings and you want the converted data to be encoded
508 |  |  |  |  | in UTF-8, you should use C<encode_json> or C<JSON> module object with C<utf8> enable.
509 |  |  |  |  |
510 |  |  |  |  | print encode_json( $perl_scalar ); # to a network? file? or display?
511 |  |  |  |  | # or
512 |  |  |  |  | print $json->utf8->encode( $perl_scalar );
513 |  |  |  |  |
514 |  |  |  |  | If C<$perl_scalar> does not contain UNICODE but C<$encoding>-encoded strings
515 |  |  |  |  | for some reason, then its characters are regarded as B<latin1> for perl
516 |  |  |  |  | (because it does not concern with your $encoding).
517 |  |  |  |  | You B<cannot> use C<encode_json> nor C<JSON> module object with C<utf8> enable.
518 |  |  |  |  | Instead of them, you use C<JSON> module object with C<utf8> disable or C<to_json>.
519 |  |  |  |  | Note that the resulted text is a UNICODE string but no problem to print it.
520 |  |  |  |  |
521 |  |  |  |  | # $perl_scalar contains $encoding encoded string values
522 |  |  |  |  | $unicode_json_text = $json->utf8(0)->encode( $perl_scalar );
523 |  |  |  |  | # or
524 |  |  |  |  | $unicode_json_text = to_json( $perl_scalar );
525 |  |  |  |  | # $unicode_json_text consists of characters less than 0x100
526 |  |  |  |  | print $unicode_json_text;
527 |  |  |  |  |
528 |  |  |  |  | Or C<decode $encoding> all string values and C<encode_json>:
529 |  |  |  |  |
530 |  |  |  |  | $perl_scalar->{ foo } = decode( $encoding, $perl_scalar->{ foo } );
531 |  |  |  |  | # ... do it to each string values, then encode_json
532 |  |  |  |  | $json_text = encode_json( $perl_scalar );
533 |  |  |  |  |
534 |  |  |  |  | This method is a proper way but probably not efficient.
535 |  |  |  |  |
536 |  |  |  |  | See to L<Encode>, L<perluniintro>.
537 |  |  |  |  |
538 |  |  |  |  |
539 |  |  |  |  | =head1 COMMON OBJECT-ORIENTED INTERFACE
540 |  |  |  |  |
541 |  |  |  |  | =head2 new
542 |  |  |  |  |
543 |  |  |  |  | $json = new JSON
544 |  |  |  |  |
545 |  |  |  |  | Returns a new C<JSON> object inherited from either JSON::XS or JSON::PP
546 |  |  |  |  | that can be used to de/encode JSON strings.
547 |  |  |  |  |
548 |  |  |  |  | All boolean flags described below are by default I<disabled>.
549 |  |  |  |  |
550 |  |  |  |  | The mutators for flags all return the JSON object again and thus calls can
551 |  |  |  |  | be chained:
552 |  |  |  |  |
553 |  |  |  |  | my $json = JSON->new->utf8->space_after->encode({a => [1,2]})
554 |  |  |  |  | => {"a": [1, 2]}
555 |  |  |  |  |
556 |  |  |  |  | =head2 ascii
557 |  |  |  |  |
558 |  |  |  |  | $json = $json->ascii([$enable])
559 |  |  |  |  |
560 |  |  |  |  | $enabled = $json->get_ascii
561 |  |  |  |  |
562 |  |  |  |  | If $enable is true (or missing), then the encode method will not generate characters outside
563 |  |  |  |  | the code range 0..127. Any Unicode characters outside that range will be escaped using either
564 |  |  |  |  | a single \uXXXX or a double \uHHHH\uLLLLL escape sequence, as per RFC4627.
565 |  |  |  |  |
566 |  |  |  |  | If $enable is false, then the encode method will not escape Unicode characters unless
567 |  |  |  |  | required by the JSON syntax or other flags. This results in a faster and more compact format.
568 |  |  |  |  |
569 |  |  |  |  | This feature depends on the used Perl version and environment.
570 |  |  |  |  |
571 |  |  |  |  | See to L<JSON::PP/UNICODE HANDLING ON PERLS> if the backend is PP.
572 |  |  |  |  |
573 |  |  |  |  | JSON->new->ascii(1)->encode([chr 0x10401])
574 |  |  |  |  | => ["\ud801\udc01"]
575 |  |  |  |  |
576 |  |  |  |  | =head2 latin1
577 |  |  |  |  |
578 |  |  |  |  | $json = $json->latin1([$enable])
579 |  |  |  |  |
580 |  |  |  |  | $enabled = $json->get_latin1
581 |  |  |  |  |
582 |  |  |  |  | If $enable is true (or missing), then the encode method will encode the resulting JSON
583 |  |  |  |  | text as latin1 (or iso-8859-1), escaping any characters outside the code range 0..255.
584 |  |  |  |  |
585 |  |  |  |  | If $enable is false, then the encode method will not escape Unicode characters
586 |  |  |  |  | unless required by the JSON syntax or other flags.
587 |  |  |  |  |
588 |  |  |  |  | JSON->new->latin1->encode (["\x{89}\x{abc}"]
589 |  |  |  |  | => ["\x{89}\\u0abc"] # (perl syntax, U+abc escaped, U+89 not)
590 |  |  |  |  |
591 |  |  |  |  | =head2 utf8
592 |  |  |  |  |
593 |  |  |  |  | $json = $json->utf8([$enable])
594 |  |  |  |  |
595 |  |  |  |  | $enabled = $json->get_utf8
596 |  |  |  |  |
597 |  |  |  |  | If $enable is true (or missing), then the encode method will encode the JSON result
598 |  |  |  |  | into UTF-8, as required by many protocols, while the decode method expects to be handled
599 |  |  |  |  | an UTF-8-encoded string. Please note that UTF-8-encoded strings do not contain any
600 |  |  |  |  | characters outside the range 0..255, they are thus useful for bytewise/binary I/O.
601 |  |  |  |  |
602 |  |  |  |  | In future versions, enabling this option might enable autodetection of the UTF-16 and UTF-32
603 |  |  |  |  | encoding families, as described in RFC4627.
604 |  |  |  |  |
605 |  |  |  |  | If $enable is false, then the encode method will return the JSON string as a (non-encoded)
606 |  |  |  |  | Unicode string, while decode expects thus a Unicode string. Any decoding or encoding
607 |  |  |  |  | (e.g. to UTF-8 or UTF-16) needs to be done yourself, e.g. using the Encode module.
608 |  |  |  |  |
609 |  |  |  |  |
610 |  |  |  |  | Example, output UTF-16BE-encoded JSON:
611 |  |  |  |  |
612 |  |  |  |  | use Encode;
613 |  |  |  |  | $jsontext = encode "UTF-16BE", JSON::XS->new->encode ($object);
614 |  |  |  |  |
615 |  |  |  |  | Example, decode UTF-32LE-encoded JSON:
616 |  |  |  |  |
617 |  |  |  |  | use Encode;
618 |  |  |  |  | $object = JSON::XS->new->decode (decode "UTF-32LE", $jsontext);
619 |  |  |  |  |
620 |  |  |  |  | See to L<JSON::PP/UNICODE HANDLING ON PERLS> if the backend is PP.
621 |  |  |  |  |
622 |  |  |  |  |
623 |  |  |  |  | =head2 pretty
624 |  |  |  |  |
625 |  |  |  |  | $json = $json->pretty([$enable])
626 |  |  |  |  |
627 |  |  |  |  | This enables (or disables) all of the C<indent>, C<space_before> and
628 |  |  |  |  | C<space_after> (and in the future possibly more) flags in one call to
629 |  |  |  |  | generate the most readable (or most compact) form possible.
630 |  |  |  |  |
631 |  |  |  |  | Equivalent to:
632 |  |  |  |  |
633 |  |  |  |  | $json->indent->space_before->space_after
634 |  |  |  |  |
635 |  |  |  |  | The indent space length is three and JSON::XS cannot change the indent
636 |  |  |  |  | space length.
637 |  |  |  |  |
638 |  |  |  |  | =head2 indent
639 |  |  |  |  |
640 |  |  |  |  | $json = $json->indent([$enable])
641 |  |  |  |  |
642 |  |  |  |  | $enabled = $json->get_indent
643 |  |  |  |  |
644 |  |  |  |  | If C<$enable> is true (or missing), then the C<encode> method will use a multiline
645 |  |  |  |  | format as output, putting every array member or object/hash key-value pair
646 |  |  |  |  | into its own line, identing them properly.
647 |  |  |  |  |
648 |  |  |  |  | If C<$enable> is false, no newlines or indenting will be produced, and the
649 |  |  |  |  | resulting JSON text is guarenteed not to contain any C<newlines>.
650 |  |  |  |  |
651 |  |  |  |  | This setting has no effect when decoding JSON texts.
652 |  |  |  |  |
653 |  |  |  |  | The indent space length is three.
654 |  |  |  |  | With JSON::PP, you can also access C<indent_length> to change indent space length.
655 |  |  |  |  |
656 |  |  |  |  |
657 |  |  |  |  | =head2 space_before
658 |  |  |  |  |
659 |  |  |  |  | $json = $json->space_before([$enable])
660 |  |  |  |  |
661 |  |  |  |  | $enabled = $json->get_space_before
662 |  |  |  |  |
663 |  |  |  |  | If C<$enable> is true (or missing), then the C<encode> method will add an extra
664 |  |  |  |  | optional space before the C<:> separating keys from values in JSON objects.
665 |  |  |  |  |
666 |  |  |  |  | If C<$enable> is false, then the C<encode> method will not add any extra
667 |  |  |  |  | space at those places.
668 |  |  |  |  |
669 |  |  |  |  | This setting has no effect when decoding JSON texts.
670 |  |  |  |  |
671 |  |  |  |  | Example, space_before enabled, space_after and indent disabled:
672 |  |  |  |  |
673 |  |  |  |  | {"key" :"value"}
674 |  |  |  |  |
675 |  |  |  |  |
676 |  |  |  |  | =head2 space_after
677 |  |  |  |  |
678 |  |  |  |  | $json = $json->space_after([$enable])
679 |  |  |  |  |
680 |  |  |  |  | $enabled = $json->get_space_after
681 |  |  |  |  |
682 |  |  |  |  | If C<$enable> is true (or missing), then the C<encode> method will add an extra
683 |  |  |  |  | optional space after the C<:> separating keys from values in JSON objects
684 |  |  |  |  | and extra whitespace after the C<,> separating key-value pairs and array
685 |  |  |  |  | members.
686 |  |  |  |  |
687 |  |  |  |  | If C<$enable> is false, then the C<encode> method will not add any extra
688 |  |  |  |  | space at those places.
689 |  |  |  |  |
690 |  |  |  |  | This setting has no effect when decoding JSON texts.
691 |  |  |  |  |
692 |  |  |  |  | Example, space_before and indent disabled, space_after enabled:
693 |  |  |  |  |
694 |  |  |  |  | {"key": "value"}
695 |  |  |  |  |
696 |  |  |  |  |
697 |  |  |  |  | =head2 relaxed
698 |  |  |  |  |
699 |  |  |  |  | $json = $json->relaxed([$enable])
700 |  |  |  |  |
701 |  |  |  |  | $enabled = $json->get_relaxed
702 |  |  |  |  |
703 |  |  |  |  | If C<$enable> is true (or missing), then C<decode> will accept some
704 |  |  |  |  | extensions to normal JSON syntax (see below). C<encode> will not be
705 |  |  |  |  | affected in anyway. I<Be aware that this option makes you accept invalid
706 |  |  |  |  | JSON texts as if they were valid!>. I suggest only to use this option to
707 |  |  |  |  | parse application-specific files written by humans (configuration files,
708 |  |  |  |  | resource files etc.)
709 |  |  |  |  |
710 |  |  |  |  | If C<$enable> is false (the default), then C<decode> will only accept
711 |  |  |  |  | valid JSON texts.
712 |  |  |  |  |
713 |  |  |  |  | Currently accepted extensions are:
714 |  |  |  |  |
715 |  |  |  |  | =over 4
716 |  |  |  |  |
717 |  |  |  |  | =item * list items can have an end-comma
718 |  |  |  |  |
719 |  |  |  |  | JSON I<separates> array elements and key-value pairs with commas. This
720 |  |  |  |  | can be annoying if you write JSON texts manually and want to be able to
721 |  |  |  |  | quickly append elements, so this extension accepts comma at the end of
722 |  |  |  |  | such items not just between them:
723 |  |  |  |  |
724 |  |  |  |  | [
725 |  |  |  |  | 1,
726 |  |  |  |  | 2, <- this comma not normally allowed
727 |  |  |  |  | ]
728 |  |  |  |  | {
729 |  |  |  |  | "k1": "v1",
730 |  |  |  |  | "k2": "v2", <- this comma not normally allowed
731 |  |  |  |  | }
732 |  |  |  |  |
733 |  |  |  |  | =item * shell-style '#'-comments
734 |  |  |  |  |
735 |  |  |  |  | Whenever JSON allows whitespace, shell-style comments are additionally
736 |  |  |  |  | allowed. They are terminated by the first carriage-return or line-feed
737 |  |  |  |  | character, after which more white-space and comments are allowed.
738 |  |  |  |  |
739 |  |  |  |  | [
740 |  |  |  |  | 1, # this comment not allowed in JSON
741 |  |  |  |  | # neither this one...
742 |  |  |  |  | ]
743 |  |  |  |  |
744 |  |  |  |  | =back
745 |  |  |  |  |
746 |  |  |  |  |
747 |  |  |  |  | =head2 canonical
748 |  |  |  |  |
749 |  |  |  |  | $json = $json->canonical([$enable])
750 |  |  |  |  |
751 |  |  |  |  | $enabled = $json->get_canonical
752 |  |  |  |  |
753 |  |  |  |  | If C<$enable> is true (or missing), then the C<encode> method will output JSON objects
754 |  |  |  |  | by sorting their keys. This is adding a comparatively high overhead.
755 |  |  |  |  |
756 |  |  |  |  | If C<$enable> is false, then the C<encode> method will output key-value
757 |  |  |  |  | pairs in the order Perl stores them (which will likely change between runs
758 |  |  |  |  | of the same script).
759 |  |  |  |  |
760 |  |  |  |  | This option is useful if you want the same data structure to be encoded as
761 |  |  |  |  | the same JSON text (given the same overall settings). If it is disabled,
762 |  |  |  |  | the same hash might be encoded differently even if contains the same data,
763 |  |  |  |  | as key-value pairs have no inherent ordering in Perl.
764 |  |  |  |  |
765 |  |  |  |  | This setting has no effect when decoding JSON texts.
766 |  |  |  |  |
767 |  |  |  |  | =head2 allow_nonref
768 |  |  |  |  |
769 |  |  |  |  | $json = $json->allow_nonref([$enable])
770 |  |  |  |  |
771 |  |  |  |  | $enabled = $json->get_allow_nonref
772 |  |  |  |  |
773 |  |  |  |  | If C<$enable> is true (or missing), then the C<encode> method can convert a
774 |  |  |  |  | non-reference into its corresponding string, number or null JSON value,
775 |  |  |  |  | which is an extension to RFC4627. Likewise, C<decode> will accept those JSON
776 |  |  |  |  | values instead of croaking.
777 |  |  |  |  |
778 |  |  |  |  | If C<$enable> is false, then the C<encode> method will croak if it isn't
779 |  |  |  |  | passed an arrayref or hashref, as JSON texts must either be an object
780 |  |  |  |  | or array. Likewise, C<decode> will croak if given something that is not a
781 |  |  |  |  | JSON object or array.
782 |  |  |  |  |
783 |  |  |  |  | JSON->new->allow_nonref->encode ("Hello, World!")
784 |  |  |  |  | => "Hello, World!"
785 |  |  |  |  |
786 |  |  |  |  | =head2 allow_unknown
787 |  |  |  |  |
788 |  |  |  |  | $json = $json->allow_unknown ([$enable])
789 |  |  |  |  |
790 |  |  |  |  | $enabled = $json->get_allow_unknown
791 |  |  |  |  |
792 |  |  |  |  | If $enable is true (or missing), then "encode" will *not* throw an
793 |  |  |  |  | exception when it encounters values it cannot represent in JSON (for
794 |  |  |  |  | example, filehandles) but instead will encode a JSON "null" value.
795 |  |  |  |  | Note that blessed objects are not included here and are handled
796 |  |  |  |  | separately by c<allow_nonref>.
797 |  |  |  |  |
798 |  |  |  |  | If $enable is false (the default), then "encode" will throw an
799 |  |  |  |  | exception when it encounters anything it cannot encode as JSON.
800 |  |  |  |  |
801 |  |  |  |  | This option does not affect "decode" in any way, and it is
802 |  |  |  |  | recommended to leave it off unless you know your communications
803 |  |  |  |  | partner.
804 |  |  |  |  |
805 |  |  |  |  | =head2 allow_blessed
806 |  |  |  |  |
807 |  |  |  |  | $json = $json->allow_blessed([$enable])
808 |  |  |  |  |
809 |  |  |  |  | $enabled = $json->get_allow_blessed
810 |  |  |  |  |
811 |  |  |  |  | If C<$enable> is true (or missing), then the C<encode> method will not
812 |  |  |  |  | barf when it encounters a blessed reference. Instead, the value of the
813 |  |  |  |  | B<convert_blessed> option will decide whether C<null> (C<convert_blessed>
814 |  |  |  |  | disabled or no C<TO_JSON> method found) or a representation of the
815 |  |  |  |  | object (C<convert_blessed> enabled and C<TO_JSON> method found) is being
816 |  |  |  |  | encoded. Has no effect on C<decode>.
817 |  |  |  |  |
818 |  |  |  |  | If C<$enable> is false (the default), then C<encode> will throw an
819 |  |  |  |  | exception when it encounters a blessed object.
820 |  |  |  |  |
821 |  |  |  |  |
822 |  |  |  |  | =head2 convert_blessed
823 |  |  |  |  |
824 |  |  |  |  | $json = $json->convert_blessed([$enable])
825 |  |  |  |  |
826 |  |  |  |  | $enabled = $json->get_convert_blessed
827 |  |  |  |  |
828 |  |  |  |  | If C<$enable> is true (or missing), then C<encode>, upon encountering a
829 |  |  |  |  | blessed object, will check for the availability of the C<TO_JSON> method
830 |  |  |  |  | on the object's class. If found, it will be called in scalar context
831 |  |  |  |  | and the resulting scalar will be encoded instead of the object. If no
832 |  |  |  |  | C<TO_JSON> method is found, the value of C<allow_blessed> will decide what
833 |  |  |  |  | to do.
834 |  |  |  |  |
835 |  |  |  |  | The C<TO_JSON> method may safely call die if it wants. If C<TO_JSON>
836 |  |  |  |  | returns other blessed objects, those will be handled in the same
837 |  |  |  |  | way. C<TO_JSON> must take care of not causing an endless recursion cycle
838 |  |  |  |  | (== crash) in this case. The name of C<TO_JSON> was chosen because other
839 |  |  |  |  | methods called by the Perl core (== not by the user of the object) are
840 |  |  |  |  | usually in upper case letters and to avoid collisions with the C<to_json>
841 |  |  |  |  | function or method.
842 |  |  |  |  |
843 |  |  |  |  | This setting does not yet influence C<decode> in any way.
844 |  |  |  |  |
845 |  |  |  |  | If C<$enable> is false, then the C<allow_blessed> setting will decide what
846 |  |  |  |  | to do when a blessed object is found.
847 |  |  |  |  |
848 |  |  |  |  | =over
849 |  |  |  |  |
850 |  |  |  |  | =item convert_blessed_universally mode
851 |  |  |  |  |
852 |  |  |  |  | If use C<JSON> with C<-convert_blessed_universally>, the C<UNIVERSAL::TO_JSON>
853 |  |  |  |  | subroutine is defined as the below code:
854 |  |  |  |  |
855 |  |  |  |  | *UNIVERSAL::TO_JSON = sub {
856 |  |  |  |  | my $b_obj = B::svref_2object( $_[0] );
857 |  |  |  |  | return $b_obj->isa('B::HV') ? { %{ $_[0] } }
858 |  |  |  |  | : $b_obj->isa('B::AV') ? [ @{ $_[0] } ]
859 |  |  |  |  | : undef
860 |  |  |  |  | ;
861 |  |  |  |  | }
862 |  |  |  |  |
863 |  |  |  |  | This will cause that C<encode> method converts simple blessed objects into
864 |  |  |  |  | JSON objects as non-blessed object.
865 |  |  |  |  |
866 |  |  |  |  | JSON -convert_blessed_universally;
867 |  |  |  |  | $json->allow_blessed->convert_blessed->encode( $blessed_object )
868 |  |  |  |  |
869 |  |  |  |  | This feature is experimental and may be removed in the future.
870 |  |  |  |  |
871 |  |  |  |  | =back
872 |  |  |  |  |
873 |  |  |  |  | =head2 filter_json_object
874 |  |  |  |  |
875 |  |  |  |  | $json = $json->filter_json_object([$coderef])
876 |  |  |  |  |
877 |  |  |  |  | When C<$coderef> is specified, it will be called from C<decode> each
878 |  |  |  |  | time it decodes a JSON object. The only argument passed to the coderef
879 |  |  |  |  | is a reference to the newly-created hash. If the code references returns
880 |  |  |  |  | a single scalar (which need not be a reference), this value
881 |  |  |  |  | (i.e. a copy of that scalar to avoid aliasing) is inserted into the
882 |  |  |  |  | deserialised data structure. If it returns an empty list
883 |  |  |  |  | (NOTE: I<not> C<undef>, which is a valid scalar), the original deserialised
884 |  |  |  |  | hash will be inserted. This setting can slow down decoding considerably.
885 |  |  |  |  |
886 |  |  |  |  | When C<$coderef> is omitted or undefined, any existing callback will
887 |  |  |  |  | be removed and C<decode> will not change the deserialised hash in any
888 |  |  |  |  | way.
889 |  |  |  |  |
890 |  |  |  |  | Example, convert all JSON objects into the integer 5:
891 |  |  |  |  |
892 |  |  |  |  | my $js = JSON->new->filter_json_object (sub { 5 });
893 |  |  |  |  | # returns [5]
894 |  |  |  |  | $js->decode ('[{}]'); # the given subroutine takes a hash reference.
895 |  |  |  |  | # throw an exception because allow_nonref is not enabled
896 |  |  |  |  | # so a lone 5 is not allowed.
897 |  |  |  |  | $js->decode ('{"a":1, "b":2}');
898 |  |  |  |  |
899 |  |  |  |  |
900 |  |  |  |  | =head2 filter_json_single_key_object
901 |  |  |  |  |
902 |  |  |  |  | $json = $json->filter_json_single_key_object($key [=> $coderef])
903 |  |  |  |  |
904 |  |  |  |  | Works remotely similar to C<filter_json_object>, but is only called for
905 |  |  |  |  | JSON objects having a single key named C<$key>.
906 |  |  |  |  |
907 |  |  |  |  | This C<$coderef> is called before the one specified via
908 |  |  |  |  | C<filter_json_object>, if any. It gets passed the single value in the JSON
909 |  |  |  |  | object. If it returns a single value, it will be inserted into the data
910 |  |  |  |  | structure. If it returns nothing (not even C<undef> but the empty list),
911 |  |  |  |  | the callback from C<filter_json_object> will be called next, as if no
912 |  |  |  |  | single-key callback were specified.
913 |  |  |  |  |
914 |  |  |  |  | If C<$coderef> is omitted or undefined, the corresponding callback will be
915 |  |  |  |  | disabled. There can only ever be one callback for a given key.
916 |  |  |  |  |
917 |  |  |  |  | As this callback gets called less often then the C<filter_json_object>
918 |  |  |  |  | one, decoding speed will not usually suffer as much. Therefore, single-key
919 |  |  |  |  | objects make excellent targets to serialise Perl objects into, especially
920 |  |  |  |  | as single-key JSON objects are as close to the type-tagged value concept
921 |  |  |  |  | as JSON gets (it's basically an ID/VALUE tuple). Of course, JSON does not
922 |  |  |  |  | support this in any way, so you need to make sure your data never looks
923 |  |  |  |  | like a serialised Perl hash.
924 |  |  |  |  |
925 |  |  |  |  | Typical names for the single object key are C<__class_whatever__>, or
926 |  |  |  |  | C<$__dollars_are_rarely_used__$> or C<}ugly_brace_placement>, or even
927 |  |  |  |  | things like C<__class_md5sum(classname)__>, to reduce the risk of clashing
928 |  |  |  |  | with real hashes.
929 |  |  |  |  |
930 |  |  |  |  | Example, decode JSON objects of the form C<< { "__widget__" => <id> } >>
931 |  |  |  |  | into the corresponding C<< $WIDGET{<id>} >> object:
932 |  |  |  |  |
933 |  |  |  |  | # return whatever is in $WIDGET{5}:
934 |  |  |  |  | JSON
935 |  |  |  |  | ->new
936 |  |  |  |  | ->filter_json_single_key_object (__widget__ => sub {
937 |  |  |  |  | $WIDGET{ $_[0] }
938 |  |  |  |  | })
939 |  |  |  |  | ->decode ('{"__widget__": 5')
940 |  |  |  |  |
941 |  |  |  |  | # this can be used with a TO_JSON method in some "widget" class
942 |  |  |  |  | # for serialisation to json:
943 |  |  |  |  | sub WidgetBase::TO_JSON {
944 |  |  |  |  | my ($self) = @_;
945 |  |  |  |  |
946 |  |  |  |  | unless ($self->{id}) {
947 |  |  |  |  | $self->{id} = ..get..some..id..;
948 |  |  |  |  | $WIDGET{$self->{id}} = $self;
949 |  |  |  |  | }
950 |  |  |  |  |
951 |  |  |  |  | { __widget__ => $self->{id} }
952 |  |  |  |  | }
953 |  |  |  |  |
954 |  |  |  |  |
955 |  |  |  |  | =head2 shrink
956 |  |  |  |  |
957 |  |  |  |  | $json = $json->shrink([$enable])
958 |  |  |  |  |
959 |  |  |  |  | $enabled = $json->get_shrink
960 |  |  |  |  |
961 |  |  |  |  | With JSON::XS, this flag resizes strings generated by either
962 |  |  |  |  | C<encode> or C<decode> to their minimum size possible. This can save
963 |  |  |  |  | memory when your JSON texts are either very very long or you have many
964 |  |  |  |  | short strings. It will also try to downgrade any strings to octet-form
965 |  |  |  |  | if possible: perl stores strings internally either in an encoding called
966 |  |  |  |  | UTF-X or in octet-form. The latter cannot store everything but uses less
967 |  |  |  |  | space in general (and some buggy Perl or C code might even rely on that
968 |  |  |  |  | internal representation being used).
969 |  |  |  |  |
970 |  |  |  |  | With JSON::PP, it is noop about resizing strings but tries
971 |  |  |  |  | C<utf8::downgrade> to the returned string by C<encode>. See to L<utf8>.
972 |  |  |  |  |
973 |  |  |  |  | See to L<JSON::XS/OBJECT-ORIENTED INTERFACE> and L<JSON::PP/METHODS>.
974 |  |  |  |  |
975 |  |  |  |  | =head2 max_depth
976 |  |  |  |  |
977 |  |  |  |  | $json = $json->max_depth([$maximum_nesting_depth])
978 |  |  |  |  |
979 |  |  |  |  | $max_depth = $json->get_max_depth
980 |  |  |  |  |
981 |  |  |  |  | Sets the maximum nesting level (default C<512>) accepted while encoding
982 |  |  |  |  | or decoding. If a higher nesting level is detected in JSON text or a Perl
983 |  |  |  |  | data structure, then the encoder and decoder will stop and croak at that
984 |  |  |  |  | point.
985 |  |  |  |  |
986 |  |  |  |  | Nesting level is defined by number of hash- or arrayrefs that the encoder
987 |  |  |  |  | needs to traverse to reach a given point or the number of C<{> or C<[>
988 |  |  |  |  | characters without their matching closing parenthesis crossed to reach a
989 |  |  |  |  | given character in a string.
990 |  |  |  |  |
991 |  |  |  |  | If no argument is given, the highest possible setting will be used, which
992 |  |  |  |  | is rarely useful.
993 |  |  |  |  |
994 |  |  |  |  | Note that nesting is implemented by recursion in C. The default value has
995 |  |  |  |  | been chosen to be as large as typical operating systems allow without
996 |  |  |  |  | crashing. (JSON::XS)
997 |  |  |  |  |
998 |  |  |  |  | With JSON::PP as the backend, when a large value (100 or more) was set and
999 |  |  |  |  | it de/encodes a deep nested object/text, it may raise a warning
1000 |  |  |  |  | 'Deep recursion on subroutin' at the perl runtime phase.
1001 |  |  |  |  |
1002 |  |  |  |  | See L<JSON::XS/SECURITY CONSIDERATIONS> for more info on why this is useful.
1003 |  |  |  |  |
1004 |  |  |  |  | =head2 max_size
1005 |  |  |  |  |
1006 |  |  |  |  | $json = $json->max_size([$maximum_string_size])
1007 |  |  |  |  |
1008 |  |  |  |  | $max_size = $json->get_max_size
1009 |  |  |  |  |
1010 |  |  |  |  | Set the maximum length a JSON text may have (in bytes) where decoding is
1011 |  |  |  |  | being attempted. The default is C<0>, meaning no limit. When C<decode>
1012 |  |  |  |  | is called on a string that is longer then this many bytes, it will not
1013 |  |  |  |  | attempt to decode the string but throw an exception. This setting has no
1014 |  |  |  |  | effect on C<encode> (yet).
1015 |  |  |  |  |
1016 |  |  |  |  | If no argument is given, the limit check will be deactivated (same as when
1017 |  |  |  |  | C<0> is specified).
1018 |  |  |  |  |
1019 |  |  |  |  | See L<JSON::XS/SECURITY CONSIDERATIONS>, below, for more info on why this is useful.
1020 |  |  |  |  |
1021 |  |  |  |  | =head2 encode
1022 |  |  |  |  |
1023 |  |  |  |  | $json_text = $json->encode($perl_scalar)
1024 |  |  |  |  |
1025 |  |  |  |  | Converts the given Perl data structure (a simple scalar or a reference
1026 |  |  |  |  | to a hash or array) to its JSON representation. Simple scalars will be
1027 |  |  |  |  | converted into JSON string or number sequences, while references to arrays
1028 |  |  |  |  | become JSON arrays and references to hashes become JSON objects. Undefined
1029 |  |  |  |  | Perl values (e.g. C<undef>) become JSON C<null> values.
1030 |  |  |  |  | References to the integers C<0> and C<1> are converted into C<true> and C<false>.
1031 |  |  |  |  |
1032 |  |  |  |  | =head2 decode
1033 |  |  |  |  |
1034 |  |  |  |  | $perl_scalar = $json->decode($json_text)
1035 |  |  |  |  |
1036 |  |  |  |  | The opposite of C<encode>: expects a JSON text and tries to parse it,
1037 |  |  |  |  | returning the resulting simple scalar or reference. Croaks on error.
1038 |  |  |  |  |
1039 |  |  |  |  | JSON numbers and strings become simple Perl scalars. JSON arrays become
1040 |  |  |  |  | Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes
1041 |  |  |  |  | C<1> (C<JSON::true>), C<false> becomes C<0> (C<JSON::false>) and
1042 |  |  |  |  | C<null> becomes C<undef>.
1043 |  |  |  |  |
1044 |  |  |  |  | =head2 decode_prefix
1045 |  |  |  |  |
1046 |  |  |  |  | ($perl_scalar, $characters) = $json->decode_prefix($json_text)
1047 |  |  |  |  |
1048 |  |  |  |  | This works like the C<decode> method, but instead of raising an exception
1049 |  |  |  |  | when there is trailing garbage after the first JSON object, it will
1050 |  |  |  |  | silently stop parsing there and return the number of characters consumed
1051 |  |  |  |  | so far.
1052 |  |  |  |  |
1053 |  |  |  |  | JSON->new->decode_prefix ("[1] the tail")
1054 |  |  |  |  | => ([], 3)
1055 |  |  |  |  |
1056 |  |  |  |  | See to L<JSON::XS/OBJECT-ORIENTED INTERFACE>
1057 |  |  |  |  |
1058 |  |  |  |  | =head2 property
1059 |  |  |  |  |
1060 |  |  |  |  | $boolean = $json->property($property_name)
1061 |  |  |  |  |
1062 |  |  |  |  | Returns a boolean value about above some properties.
1063 |  |  |  |  |
1064 |  |  |  |  | The available properties are C<ascii>, C<latin1>, C<utf8>,
1065 |  |  |  |  | C<indent>,C<space_before>, C<space_after>, C<relaxed>, C<canonical>,
1066 |  |  |  |  | C<allow_nonref>, C<allow_unknown>, C<allow_blessed>, C<convert_blessed>,
1067 |  |  |  |  | C<shrink>, C<max_depth> and C<max_size>.
1068 |  |  |  |  |
1069 |  |  |  |  | $boolean = $json->property('utf8');
1070 |  |  |  |  | => 0
1071 |  |  |  |  | $json->utf8;
1072 |  |  |  |  | $boolean = $json->property('utf8');
1073 |  |  |  |  | => 1
1074 |  |  |  |  |
1075 |  |  |  |  | Sets the property with a given boolean value.
1076 |  |  |  |  |
1077 |  |  |  |  | $json = $json->property($property_name => $boolean);
1078 |  |  |  |  |
1079 |  |  |  |  | With no argumnt, it returns all the above properties as a hash reference.
1080 |  |  |  |  |
1081 |  |  |  |  | $flag_hashref = $json->property();
1082 |  |  |  |  |
1083 |  |  |  |  | =head1 INCREMENTAL PARSING
1084 |  |  |  |  |
1085 |  |  |  |  | Most of this section are copied and modified from L<JSON::XS/INCREMENTAL PARSING>.
1086 |  |  |  |  |
1087 |  |  |  |  | In some cases, there is the need for incremental parsing of JSON texts.
1088 |  |  |  |  | This module does allow you to parse a JSON stream incrementally.
1089 |  |  |  |  | It does so by accumulating text until it has a full JSON object, which
1090 |  |  |  |  | it then can decode. This process is similar to using C<decode_prefix>
1091 |  |  |  |  | to see if a full JSON object is available, but is much more efficient
1092 |  |  |  |  | (and can be implemented with a minimum of method calls).
1093 |  |  |  |  |
1094 |  |  |  |  | The backend module will only attempt to parse the JSON text once it is sure it
1095 |  |  |  |  | has enough text to get a decisive result, using a very simple but
1096 |  |  |  |  | truly incremental parser. This means that it sometimes won't stop as
1097 |  |  |  |  | early as the full parser, for example, it doesn't detect parenthese
1098 |  |  |  |  | mismatches. The only thing it guarantees is that it starts decoding as
1099 |  |  |  |  | soon as a syntactically valid JSON text has been seen. This means you need
1100 |  |  |  |  | to set resource limits (e.g. C<max_size>) to ensure the parser will stop
1101 |  |  |  |  | parsing in the presence if syntax errors.
1102 |  |  |  |  |
1103 |  |  |  |  | The following methods implement this incremental parser.
1104 |  |  |  |  |
1105 |  |  |  |  | =head2 incr_parse
1106 |  |  |  |  |
1107 |  |  |  |  | $json->incr_parse( [$string] ) # void context
1108 |  |  |  |  |
1109 |  |  |  |  | $obj_or_undef = $json->incr_parse( [$string] ) # scalar context
1110 |  |  |  |  |
1111 |  |  |  |  | @obj_or_empty = $json->incr_parse( [$string] ) # list context
1112 |  |  |  |  |
1113 |  |  |  |  | This is the central parsing function. It can both append new text and
1114 |  |  |  |  | extract objects from the stream accumulated so far (both of these
1115 |  |  |  |  | functions are optional).
1116 |  |  |  |  |
1117 |  |  |  |  | If C<$string> is given, then this string is appended to the already
1118 |  |  |  |  | existing JSON fragment stored in the C<$json> object.
1119 |  |  |  |  |
1120 |  |  |  |  | After that, if the function is called in void context, it will simply
1121 |  |  |  |  | return without doing anything further. This can be used to add more text
1122 |  |  |  |  | in as many chunks as you want.
1123 |  |  |  |  |
1124 |  |  |  |  | If the method is called in scalar context, then it will try to extract
1125 |  |  |  |  | exactly I<one> JSON object. If that is successful, it will return this
1126 |  |  |  |  | object, otherwise it will return C<undef>. If there is a parse error,
1127 |  |  |  |  | this method will croak just as C<decode> would do (one can then use
1128 |  |  |  |  | C<incr_skip> to skip the errornous part). This is the most common way of
1129 |  |  |  |  | using the method.
1130 |  |  |  |  |
1131 |  |  |  |  | And finally, in list context, it will try to extract as many objects
1132 |  |  |  |  | from the stream as it can find and return them, or the empty list
1133 |  |  |  |  | otherwise. For this to work, there must be no separators between the JSON
1134 |  |  |  |  | objects or arrays, instead they must be concatenated back-to-back. If
1135 |  |  |  |  | an error occurs, an exception will be raised as in the scalar context
1136 |  |  |  |  | case. Note that in this case, any previously-parsed JSON texts will be
1137 |  |  |  |  | lost.
1138 |  |  |  |  |
1139 |  |  |  |  | Example: Parse some JSON arrays/objects in a given string and return them.
1140 |  |  |  |  |
1141 |  |  |  |  | my @objs = JSON->new->incr_parse ("[5][7][1,2]");
1142 |  |  |  |  |
1143 |  |  |  |  | =head2 incr_text
1144 |  |  |  |  |
1145 |  |  |  |  | $lvalue_string = $json->incr_text
1146 |  |  |  |  |
1147 |  |  |  |  | This method returns the currently stored JSON fragment as an lvalue, that
1148 |  |  |  |  | is, you can manipulate it. This I<only> works when a preceding call to
1149 |  |  |  |  | C<incr_parse> in I<scalar context> successfully returned an object. Under
1150 |  |  |  |  | all other circumstances you must not call this function (I mean it.
1151 |  |  |  |  | although in simple tests it might actually work, it I<will> fail under
1152 |  |  |  |  | real world conditions). As a special exception, you can also call this
1153 |  |  |  |  | method before having parsed anything.
1154 |  |  |  |  |
1155 |  |  |  |  | This function is useful in two cases: a) finding the trailing text after a
1156 |  |  |  |  | JSON object or b) parsing multiple JSON objects separated by non-JSON text
1157 |  |  |  |  | (such as commas).
1158 |  |  |  |  |
1159 |  |  |  |  | $json->incr_text =~ s/\s*,\s*//;
1160 |  |  |  |  |
1161 |  |  |  |  | In Perl 5.005, C<lvalue> attribute is not available.
1162 |  |  |  |  | You must write codes like the below:
1163 |  |  |  |  |
1164 |  |  |  |  | $string = $json->incr_text;
1165 |  |  |  |  | $string =~ s/\s*,\s*//;
1166 |  |  |  |  | $json->incr_text( $string );
1167 |  |  |  |  |
1168 |  |  |  |  | =head2 incr_skip
1169 |  |  |  |  |
1170 |  |  |  |  | $json->incr_skip
1171 |  |  |  |  |
1172 |  |  |  |  | This will reset the state of the incremental parser and will remove the
1173 |  |  |  |  | parsed text from the input buffer. This is useful after C<incr_parse>
1174 |  |  |  |  | died, in which case the input buffer and incremental parser state is left
1175 |  |  |  |  | unchanged, to skip the text parsed so far and to reset the parse state.
1176 |  |  |  |  |
1177 |  |  |  |  | =head2 incr_reset
1178 |  |  |  |  |
1179 |  |  |  |  | $json->incr_reset
1180 |  |  |  |  |
1181 |  |  |  |  | This completely resets the incremental parser, that is, after this call,
1182 |  |  |  |  | it will be as if the parser had never parsed anything.
1183 |  |  |  |  |
1184 |  |  |  |  | This is useful if you want ot repeatedly parse JSON objects and want to
1185 |  |  |  |  | ignore any trailing data, which means you have to reset the parser after
1186 |  |  |  |  | each successful decode.
1187 |  |  |  |  |
1188 |  |  |  |  | See to L<JSON::XS/INCREMENTAL PARSING> for examples.
1189 |  |  |  |  |
1190 |  |  |  |  |
1191 |  |  |  |  | =head1 JSON::PP SUPPORT METHODS
1192 |  |  |  |  |
1193 |  |  |  |  | The below methods are JSON::PP own methods, so when C<JSON> works
1194 |  |  |  |  | with JSON::PP (i.e. the created object is a JSON::PP object), available.
1195 |  |  |  |  | See to L<JSON::PP/JSON::PP OWN METHODS> in detail.
1196 |  |  |  |  |
1197 |  |  |  |  | If you use C<JSON> with additonal C<-support_by_pp>, some methods
1198 |  |  |  |  | are available even with JSON::XS. See to L<USE PP FEATURES EVEN THOUGH XS BACKEND>.
1199 |  |  |  |  |
1200 |  |  |  |  | BEING { $ENV{PERL_JSON_BACKEND} = 'JSON::XS' }
1201 |  |  |  |  |
1202 |  |  |  |  | use JSON -support_by_pp;
1203 |  |  |  |  |
1204 |  |  |  |  | my $json = new JSON;
1205 |  |  |  |  | $json->allow_nonref->escape_slash->encode("/");
1206 |  |  |  |  |
1207 |  |  |  |  | # functional interfaces too.
1208 |  |  |  |  | print to_json(["/"], {escape_slash => 1});
1209 |  |  |  |  | print from_json('["foo"]', {utf8 => 1});
1210 |  |  |  |  |
1211 |  |  |  |  | If you do not want to all functions but C<-support_by_pp>,
1212 |  |  |  |  | use C<-no_export>.
1213 |  |  |  |  |
1214 |  |  |  |  | use JSON -support_by_pp, -no_export;
1215 |  |  |  |  | # functional interfaces are not exported.
1216 |  |  |  |  |
1217 |  |  |  |  | =head2 allow_singlequote
1218 |  |  |  |  |
1219 |  |  |  |  | $json = $json->allow_singlequote([$enable])
1220 |  |  |  |  |
1221 |  |  |  |  | If C<$enable> is true (or missing), then C<decode> will accept
1222 |  |  |  |  | any JSON strings quoted by single quotations that are invalid JSON
1223 |  |  |  |  | format.
1224 |  |  |  |  |
1225 |  |  |  |  | $json->allow_singlequote->decode({"foo":'bar'});
1226 |  |  |  |  | $json->allow_singlequote->decode({'foo':"bar"});
1227 |  |  |  |  | $json->allow_singlequote->decode({'foo':'bar'});
1228 |  |  |  |  |
1229 |  |  |  |  | As same as the C<relaxed> option, this option may be used to parse
1230 |  |  |  |  | application-specific files written by humans.
1231 |  |  |  |  |
1232 |  |  |  |  | =head2 allow_barekey
1233 |  |  |  |  |
1234 |  |  |  |  | $json = $json->allow_barekey([$enable])
1235 |  |  |  |  |
1236 |  |  |  |  | If C<$enable> is true (or missing), then C<decode> will accept
1237 |  |  |  |  | bare keys of JSON object that are invalid JSON format.
1238 |  |  |  |  |
1239 |  |  |  |  | As same as the C<relaxed> option, this option may be used to parse
1240 |  |  |  |  | application-specific files written by humans.
1241 |  |  |  |  |
1242 |  |  |  |  | $json->allow_barekey->decode('{foo:"bar"}');
1243 |  |  |  |  |
1244 |  |  |  |  | =head2 allow_bignum
1245 |  |  |  |  |
1246 |  |  |  |  | $json = $json->allow_bignum([$enable])
1247 |  |  |  |  |
1248 |  |  |  |  | If C<$enable> is true (or missing), then C<decode> will convert
1249 |  |  |  |  | the big integer Perl cannot handle as integer into a L<Math::BigInt>
1250 |  |  |  |  | object and convert a floating number (any) into a L<Math::BigFloat>.
1251 |  |  |  |  |
1252 |  |  |  |  | On the contary, C<encode> converts C<Math::BigInt> objects and C<Math::BigFloat>
1253 |  |  |  |  | objects into JSON numbers with C<allow_blessed> enable.
1254 |  |  |  |  |
1255 |  |  |  |  | $json->allow_nonref->allow_blessed->allow_bignum;
1256 |  |  |  |  | $bigfloat = $json->decode('2.000000000000000000000000001');
1257 |  |  |  |  | print $json->encode($bigfloat);
1258 |  |  |  |  | # => 2.000000000000000000000000001
1259 |  |  |  |  |
1260 |  |  |  |  | See to L<MAPPING> aboout the conversion of JSON number.
1261 |  |  |  |  |
1262 |  |  |  |  | =head2 loose
1263 |  |  |  |  |
1264 |  |  |  |  | $json = $json->loose([$enable])
1265 |  |  |  |  |
1266 |  |  |  |  | The unescaped [\x00-\x1f\x22\x2f\x5c] strings are invalid in JSON strings
1267 |  |  |  |  | and the module doesn't allow to C<decode> to these (except for \x2f).
1268 |  |  |  |  | If C<$enable> is true (or missing), then C<decode> will accept these
1269 |  |  |  |  | unescaped strings.
1270 |  |  |  |  |
1271 |  |  |  |  | $json->loose->decode(qq|["abc
1272 |  |  |  |  | def"]|);
1273 |  |  |  |  |
1274 |  |  |  |  | See to L<JSON::PP/JSON::PP OWN METHODS>.
1275 |  |  |  |  |
1276 |  |  |  |  | =head2 escape_slash
1277 |  |  |  |  |
1278 |  |  |  |  | $json = $json->escape_slash([$enable])
1279 |  |  |  |  |
1280 |  |  |  |  | According to JSON Grammar, I<slash> (U+002F) is escaped. But by default
1281 |  |  |  |  | JSON backend modules encode strings without escaping slash.
1282 |  |  |  |  |
1283 |  |  |  |  | If C<$enable> is true (or missing), then C<encode> will escape slashes.
1284 |  |  |  |  |
1285 |  |  |  |  | =head2 indent_length
1286 |  |  |  |  |
1287 |  |  |  |  | $json = $json->indent_length($length)
1288 |  |  |  |  |
1289 |  |  |  |  | With JSON::XS, The indent space length is 3 and cannot be changed.
1290 |  |  |  |  | With JSON::PP, it sets the indent space length with the given $length.
1291 |  |  |  |  | The default is 3. The acceptable range is 0 to 15.
1292 |  |  |  |  |
1293 |  |  |  |  | =head2 sort_by
1294 |  |  |  |  |
1295 |  |  |  |  | $json = $json->sort_by($function_name)
1296 |  |  |  |  | $json = $json->sort_by($subroutine_ref)
1297 |  |  |  |  |
1298 |  |  |  |  | If $function_name or $subroutine_ref are set, its sort routine are used.
1299 |  |  |  |  |
1300 |  |  |  |  | $js = $pc->sort_by(sub { $JSON::PP::a cmp $JSON::PP::b })->encode($obj);
1301 |  |  |  |  | # is($js, q|{"a":1,"b":2,"c":3,"d":4,"e":5,"f":6,"g":7,"h":8,"i":9}|);
1302 |  |  |  |  |
1303 |  |  |  |  | $js = $pc->sort_by('own_sort')->encode($obj);
1304 |  |  |  |  | # is($js, q|{"a":1,"b":2,"c":3,"d":4,"e":5,"f":6,"g":7,"h":8,"i":9}|);
1305 |  |  |  |  |
1306 |  |  |  |  | sub JSON::PP::own_sort { $JSON::PP::a cmp $JSON::PP::b }
1307 |  |  |  |  |
1308 |  |  |  |  | As the sorting routine runs in the JSON::PP scope, the given
1309 |  |  |  |  | subroutine name and the special variables C<$a>, C<$b> will begin
1310 |  |  |  |  | with 'JSON::PP::'.
1311 |  |  |  |  |
1312 |  |  |  |  | If $integer is set, then the effect is same as C<canonical> on.
1313 |  |  |  |  |
1314 |  |  |  |  | See to L<JSON::PP/JSON::PP OWN METHODS>.
1315 |  |  |  |  |
1316 |  |  |  |  | =head1 MAPPING
1317 |  |  |  |  |
1318 |  |  |  |  | This section is copied from JSON::XS and modified to C<JSON>.
1319 |  |  |  |  | JSON::XS and JSON::PP mapping mechanisms are almost equivalent.
1320 |  |  |  |  |
1321 |  |  |  |  | See to L<JSON::XS/MAPPING>.
1322 |  |  |  |  |
1323 |  |  |  |  | =head2 JSON -> PERL
1324 |  |  |  |  |
1325 |  |  |  |  | =over 4
1326 |  |  |  |  |
1327 |  |  |  |  | =item object
1328 |  |  |  |  |
1329 |  |  |  |  | A JSON object becomes a reference to a hash in Perl. No ordering of object
1330 |  |  |  |  | keys is preserved (JSON does not preserver object key ordering itself).
1331 |  |  |  |  |
1332 |  |  |  |  | =item array
1333 |  |  |  |  |
1334 |  |  |  |  | A JSON array becomes a reference to an array in Perl.
1335 |  |  |  |  |
1336 |  |  |  |  | =item string
1337 |  |  |  |  |
1338 |  |  |  |  | A JSON string becomes a string scalar in Perl - Unicode codepoints in JSON
1339 |  |  |  |  | are represented by the same codepoints in the Perl string, so no manual
1340 |  |  |  |  | decoding is necessary.
1341 |  |  |  |  |
1342 |  |  |  |  | =item number
1343 |  |  |  |  |
1344 |  |  |  |  | A JSON number becomes either an integer, numeric (floating point) or
1345 |  |  |  |  | string scalar in perl, depending on its range and any fractional parts. On
1346 |  |  |  |  | the Perl level, there is no difference between those as Perl handles all
1347 |  |  |  |  | the conversion details, but an integer may take slightly less memory and
1348 |  |  |  |  | might represent more values exactly than floating point numbers.
1349 |  |  |  |  |
1350 |  |  |  |  | If the number consists of digits only, C<JSON> will try to represent
1351 |  |  |  |  | it as an integer value. If that fails, it will try to represent it as
1352 |  |  |  |  | a numeric (floating point) value if that is possible without loss of
1353 |  |  |  |  | precision. Otherwise it will preserve the number as a string value (in
1354 |  |  |  |  | which case you lose roundtripping ability, as the JSON number will be
1355 |  |  |  |  | re-encoded toa JSON string).
1356 |  |  |  |  |
1357 |  |  |  |  | Numbers containing a fractional or exponential part will always be
1358 |  |  |  |  | represented as numeric (floating point) values, possibly at a loss of
1359 |  |  |  |  | precision (in which case you might lose perfect roundtripping ability, but
1360 |  |  |  |  | the JSON number will still be re-encoded as a JSON number).
1361 |  |  |  |  |
1362 |  |  |  |  | Note that precision is not accuracy - binary floating point values cannot
1363 |  |  |  |  | represent most decimal fractions exactly, and when converting from and to
1364 |  |  |  |  | floating point, C<JSON> only guarantees precision up to but not including
1365 |  |  |  |  | the leats significant bit.
1366 |  |  |  |  |
1367 |  |  |  |  | If the backend is JSON::PP and C<allow_bignum> is enable, the big integers
1368 |  |  |  |  | and the numeric can be optionally converted into L<Math::BigInt> and
1369 |  |  |  |  | L<Math::BigFloat> objects.
1370 |  |  |  |  |
1371 |  |  |  |  | =item true, false
1372 |  |  |  |  |
1373 |  |  |  |  | These JSON atoms become C<JSON::true> and C<JSON::false>,
1374 |  |  |  |  | respectively. They are overloaded to act almost exactly like the numbers
1375 |  |  |  |  | C<1> and C<0>. You can check wether a scalar is a JSON boolean by using
1376 |  |  |  |  | the C<JSON::is_bool> function.
1377 |  |  |  |  |
1378 |  |  |  |  | If C<JSON::true> and C<JSON::false> are used as strings or compared as strings,
1379 |  |  |  |  | they represent as C<true> and C<false> respectively.
1380 |  |  |  |  |
1381 |  |  |  |  | print JSON::true . "\n";
1382 |  |  |  |  | => true
1383 |  |  |  |  | print JSON::true + 1;
1384 |  |  |  |  | => 1
1385 |  |  |  |  |
1386 |  |  |  |  | ok(JSON::true eq 'true');
1387 |  |  |  |  | ok(JSON::true eq '1');
1388 |  |  |  |  | ok(JSON::true == 1);
1389 |  |  |  |  |
1390 |  |  |  |  | C<JSON> will install these missing overloading features to the backend modules.
1391 |  |  |  |  |
1392 |  |  |  |  |
1393 |  |  |  |  | =item null
1394 |  |  |  |  |
1395 |  |  |  |  | A JSON null atom becomes C<undef> in Perl.
1396 |  |  |  |  |
1397 |  |  |  |  | C<JSON::null> returns C<unddef>.
1398 |  |  |  |  |
1399 |  |  |  |  | =back
1400 |  |  |  |  |
1401 |  |  |  |  |
1402 |  |  |  |  | =head2 PERL -> JSON
1403 |  |  |  |  |
1404 |  |  |  |  | The mapping from Perl to JSON is slightly more difficult, as Perl is a
1405 |  |  |  |  | truly typeless language, so we can only guess which JSON type is meant by
1406 |  |  |  |  | a Perl value.
1407 |  |  |  |  |
1408 |  |  |  |  | =over 4
1409 |  |  |  |  |
1410 |  |  |  |  | =item hash references
1411 |  |  |  |  |
1412 |  |  |  |  | Perl hash references become JSON objects. As there is no inherent ordering
1413 |  |  |  |  | in hash keys (or JSON objects), they will usually be encoded in a
1414 |  |  |  |  | pseudo-random order that can change between runs of the same program but
1415 |  |  |  |  | stays generally the same within a single run of a program. C<JSON>
1416 |  |  |  |  | optionally sort the hash keys (determined by the I<canonical> flag), so
1417 |  |  |  |  | the same datastructure will serialise to the same JSON text (given same
1418 |  |  |  |  | settings and version of JSON::XS), but this incurs a runtime overhead
1419 |  |  |  |  | and is only rarely useful, e.g. when you want to compare some JSON text
1420 |  |  |  |  | against another for equality.
1421 |  |  |  |  |
1422 |  |  |  |  | In future, the ordered object feature will be added to JSON::PP using C<tie> mechanism.
1423 |  |  |  |  |
1424 |  |  |  |  |
1425 |  |  |  |  | =item array references
1426 |  |  |  |  |
1427 |  |  |  |  | Perl array references become JSON arrays.
1428 |  |  |  |  |
1429 |  |  |  |  | =item other references
1430 |  |  |  |  |
1431 |  |  |  |  | Other unblessed references are generally not allowed and will cause an
1432 |  |  |  |  | exception to be thrown, except for references to the integers C<0> and
1433 |  |  |  |  | C<1>, which get turned into C<false> and C<true> atoms in JSON. You can
1434 |  |  |  |  | also use C<JSON::false> and C<JSON::true> to improve readability.
1435 |  |  |  |  |
1436 |  |  |  |  | to_json [\0,JSON::true] # yields [false,true]
1437 |  |  |  |  |
1438 |  |  |  |  | =item JSON::true, JSON::false, JSON::null
1439 |  |  |  |  |
1440 |  |  |  |  | These special values become JSON true and JSON false values,
1441 |  |  |  |  | respectively. You can also use C<\1> and C<\0> directly if you want.
1442 |  |  |  |  |
1443 |  |  |  |  | JSON::null returns C<undef>.
1444 |  |  |  |  |
1445 |  |  |  |  | =item blessed objects
1446 |  |  |  |  |
1447 |  |  |  |  | Blessed objects are not directly representable in JSON. See the
1448 |  |  |  |  | C<allow_blessed> and C<convert_blessed> methods on various options on
1449 |  |  |  |  | how to deal with this: basically, you can choose between throwing an
1450 |  |  |  |  | exception, encoding the reference as if it weren't blessed, or provide
1451 |  |  |  |  | your own serialiser method.
1452 |  |  |  |  |
1453 |  |  |  |  | With C<convert_blessed_universally> mode, C<encode> converts blessed
1454 |  |  |  |  | hash references or blessed array references (contains other blessed references)
1455 |  |  |  |  | into JSON members and arrays.
1456 |  |  |  |  |
1457 |  |  |  |  | use JSON -convert_blessed_universally;
1458 |  |  |  |  | JSON->new->allow_blessed->convert_blessed->encode( $blessed_object );
1459 |  |  |  |  |
1460 |  |  |  |  | See to L<convert_blessed>.
1461 |  |  |  |  |
1462 |  |  |  |  | =item simple scalars
1463 |  |  |  |  |
1464 |  |  |  |  | Simple Perl scalars (any scalar that is not a reference) are the most
1465 |  |  |  |  | difficult objects to encode: JSON::XS and JSON::PP will encode undefined scalars as
1466 |  |  |  |  | JSON C<null> values, scalars that have last been used in a string context
1467 |  |  |  |  | before encoding as JSON strings, and anything else as number value:
1468 |  |  |  |  |
1469 |  |  |  |  | # dump as number
1470 |  |  |  |  | encode_json [2] # yields [2]
1471 |  |  |  |  | encode_json [-3.0e17] # yields [-3e+17]
1472 |  |  |  |  | my $value = 5; encode_json [$value] # yields [5]
1473 |  |  |  |  |
1474 |  |  |  |  | # used as string, so dump as string
1475 |  |  |  |  | print $value;
1476 |  |  |  |  | encode_json [$value] # yields ["5"]
1477 |  |  |  |  |
1478 |  |  |  |  | # undef becomes null
1479 |  |  |  |  | encode_json [undef] # yields [null]
1480 |  |  |  |  |
1481 |  |  |  |  | You can force the type to be a string by stringifying it:
1482 |  |  |  |  |
1483 |  |  |  |  | my $x = 3.1; # some variable containing a number
1484 |  |  |  |  | "$x"; # stringified
1485 |  |  |  |  | $x .= ""; # another, more awkward way to stringify
1486 |  |  |  |  | print $x; # perl does it for you, too, quite often
1487 |  |  |  |  |
1488 |  |  |  |  | You can force the type to be a number by numifying it:
1489 |  |  |  |  |
1490 |  |  |  |  | my $x = "3"; # some variable containing a string
1491 |  |  |  |  | $x += 0; # numify it, ensuring it will be dumped as a number
1492 |  |  |  |  | $x *= 1; # same thing, the choise is yours.
1493 |  |  |  |  |
1494 |  |  |  |  | You can not currently force the type in other, less obscure, ways.
1495 |  |  |  |  |
1496 |  |  |  |  | Note that numerical precision has the same meaning as under Perl (so
1497 |  |  |  |  | binary to decimal conversion follows the same rules as in Perl, which
1498 |  |  |  |  | can differ to other languages). Also, your perl interpreter might expose
1499 |  |  |  |  | extensions to the floating point numbers of your platform, such as
1500 |  |  |  |  | infinities or NaN's - these cannot be represented in JSON, and it is an
1501 |  |  |  |  | error to pass those in.
1502 |  |  |  |  |
1503 |  |  |  |  | =item Big Number
1504 |  |  |  |  |
1505 |  |  |  |  | If the backend is JSON::PP and C<allow_bignum> is enable,
1506 |  |  |  |  | C<encode> converts C<Math::BigInt> objects and C<Math::BigFloat>
1507 |  |  |  |  | objects into JSON numbers.
1508 |  |  |  |  |
1509 |  |  |  |  |
1510 |  |  |  |  | =back
1511 |  |  |  |  |
1512 |  |  |  |  | =head1 JSON and ECMAscript
1513 |  |  |  |  |
1514 |  |  |  |  | See to L<JSON::XS/JSON and ECMAscript>.
1515 |  |  |  |  |
1516 |  |  |  |  | =head1 JSON and YAML
1517 |  |  |  |  |
1518 |  |  |  |  | JSON is not a subset of YAML.
1519 |  |  |  |  | See to L<JSON::XS/JSON and YAML>.
1520 |  |  |  |  |
1521 |  |  |  |  |
1522 |  |  |  |  | =head1 BACKEND MODULE DECISION
1523 |  |  |  |  |
1524 |  |  |  |  | When you use C<JSON>, C<JSON> tries to C<use> JSON::XS. If this call failed, it will
1525 |  |  |  |  | C<uses> JSON::PP. The required JSON::XS version is I<2.2> or later.
1526 |  |  |  |  |
1527 |  |  |  |  | The C<JSON> constructor method returns an object inherited from the backend module,
1528 |  |  |  |  | and JSON::XS object is a blessed scaler reference while JSON::PP is a blessed hash
1529 |  |  |  |  | reference.
1530 |  |  |  |  |
1531 |  |  |  |  | So, your program should not depend on the backend module, especially
1532 |  |  |  |  | returned objects should not be modified.
1533 |  |  |  |  |
1534 |  |  |  |  | my $json = JSON->new; # XS or PP?
1535 |  |  |  |  | $json->{stash} = 'this is xs object'; # this code may raise an error!
1536 |  |  |  |  |
1537 |  |  |  |  | To check the backend module, there are some methods - C<backend>, C<is_pp> and C<is_xs>.
1538 |  |  |  |  |
1539 |  |  |  |  | JSON->backend; # 'JSON::XS' or 'JSON::PP'
1540 |  |  |  |  |
1541 |  |  |  |  | JSON->backend->is_pp: # 0 or 1
1542 |  |  |  |  |
1543 |  |  |  |  | JSON->backend->is_xs: # 1 or 0
1544 |  |  |  |  |
1545 |  |  |  |  | $json->is_xs; # 1 or 0
1546 |  |  |  |  |
1547 |  |  |  |  | $json->is_pp; # 0 or 1
1548 |  |  |  |  |
1549 |  |  |  |  |
1550 |  |  |  |  | If you set an enviornment variable C<PERL_JSON_BACKEND>, The calling action will be changed.
1551 |  |  |  |  |
1552 |  |  |  |  | =over
1553 |  |  |  |  |
1554 |  |  |  |  | =item PERL_JSON_BACKEND = 0 or PERL_JSON_BACKEND = 'JSON::PP'
1555 |  |  |  |  |
1556 |  |  |  |  | Always use JSON::PP
1557 |  |  |  |  |
1558 |  |  |  |  | =item PERL_JSON_BACKEND == 1 or PERL_JSON_BACKEND = 'JSON::XS,JSON::PP'
1559 |  |  |  |  |
1560 |  |  |  |  | (The default) Use compiled JSON::XS if it is properly compiled & installed,
1561 |  |  |  |  | otherwise use JSON::PP.
1562 |  |  |  |  |
1563 |  |  |  |  | =item PERL_JSON_BACKEND == 2 or PERL_JSON_BACKEND = 'JSON::XS'
1564 |  |  |  |  |
1565 |  |  |  |  | Always use compiled JSON::XS, die if it isn't properly compiled & installed.
1566 |  |  |  |  |
1567 |  |  |  |  | =item PERL_JSON_BACKEND = 'JSON::backportPP'
1568 |  |  |  |  |
1569 |  |  |  |  | Always use JSON::backportPP.
1570 |  |  |  |  | JSON::backportPP is JSON::PP back port module.
1571 |  |  |  |  | C<JSON> includs JSON::backportPP instead of JSON::PP.
1572 |  |  |  |  |
1573 |  |  |  |  | =back
1574 |  |  |  |  |
1575 |  |  |  |  | These ideas come from L<DBI::PurePerl> mechanism.
1576 |  |  |  |  |
1577 |  |  |  |  | example:
1578 |  |  |  |  |
1579 |  |  |  |  | BEGIN { $ENV{PERL_JSON_BACKEND} = 'JSON::PP' }
1580 |  |  |  |  | use JSON; # always uses JSON::PP
1581 |  |  |  |  |
1582 |  |  |  |  | In future, it may be able to specify another module.
1583 |  |  |  |  |
1584 |  |  |  |  | =head1 USE PP FEATURES EVEN THOUGH XS BACKEND
1585 |  |  |  |  |
1586 |  |  |  |  | Many methods are available with either JSON::XS or JSON::PP and
1587 |  |  |  |  | when the backend module is JSON::XS, if any JSON::PP specific (i.e. JSON::XS unspported)
1588 |  |  |  |  | method is called, it will C<warn> and be noop.
1589 |  |  |  |  |
1590 |  |  |  |  | But If you C<use> C<JSON> passing the optional string C<-support_by_pp>,
1591 |  |  |  |  | it makes a part of those unupported methods available.
1592 |  |  |  |  | This feature is achieved by using JSON::PP in C<de/encode>.
1593 |  |  |  |  |
1594 |  |  |  |  | BEGIN { $ENV{PERL_JSON_BACKEND} = 2 } # with JSON::XS
1595 |  |  |  |  | use JSON -support_by_pp;
1596 |  |  |  |  | my $json = new JSON;
1597 |  |  |  |  | $json->allow_nonref->escape_slash->encode("/");
1598 |  |  |  |  |
1599 |  |  |  |  | At this time, the returned object is a C<JSON::Backend::XS::Supportable>
1600 |  |  |  |  | object (re-blessed XS object), and by checking JSON::XS unsupported flags
1601 |  |  |  |  | in de/encoding, can support some unsupported methods - C<loose>, C<allow_bignum>,
1602 |  |  |  |  | C<allow_barekey>, C<allow_singlequote>, C<escape_slash> and C<indent_length>.
1603 |  |  |  |  |
1604 |  |  |  |  | When any unsupported methods are not enable, C<XS de/encode> will be
1605 |  |  |  |  | used as is. The switch is achieved by changing the symbolic tables.
1606 |  |  |  |  |
1607 |  |  |  |  | C<-support_by_pp> is effective only when the backend module is JSON::XS
1608 |  |  |  |  | and it makes the de/encoding speed down a bit.
1609 |  |  |  |  |
1610 |  |  |  |  | See to L<JSON::PP SUPPORT METHODS>.
1611 |  |  |  |  |
1612 |  |  |  |  | =head1 INCOMPATIBLE CHANGES TO OLD VERSION
1613 |  |  |  |  |
1614 |  |  |  |  | There are big incompatibility between new version (2.00) and old (1.xx).
1615 |  |  |  |  | If you use old C<JSON> 1.xx in your code, please check it.
1616 |  |  |  |  |
1617 |  |  |  |  | See to L<Transition ways from 1.xx to 2.xx.>
1618 |  |  |  |  |
1619 |  |  |  |  | =over
1620 |  |  |  |  |
1621 |  |  |  |  | =item jsonToObj and objToJson are obsoleted.
1622 |  |  |  |  |
1623 |  |  |  |  | Non Perl-style name C<jsonToObj> and C<objToJson> are obsoleted
1624 |  |  |  |  | (but not yet deleted from the source).
1625 |  |  |  |  | If you use these functions in your code, please replace them
1626 |  |  |  |  | with C<from_json> and C<to_json>.
1627 |  |  |  |  |
1628 |  |  |  |  |
1629 |  |  |  |  | =item Global variables are no longer available.
1630 |  |  |  |  |
1631 |  |  |  |  | C<JSON> class variables - C<$JSON::AUTOCONVERT>, C<$JSON::BareKey>, etc...
1632 |  |  |  |  | - are not available any longer.
1633 |  |  |  |  | Instead, various features can be used through object methods.
1634 |  |  |  |  |
1635 |  |  |  |  |
1636 |  |  |  |  | =item Package JSON::Converter and JSON::Parser are deleted.
1637 |  |  |  |  |
1638 |  |  |  |  | Now C<JSON> bundles with JSON::PP which can handle JSON more properly than them.
1639 |  |  |  |  |
1640 |  |  |  |  | =item Package JSON::NotString is deleted.
1641 |  |  |  |  |
1642 |  |  |  |  | There was C<JSON::NotString> class which represents JSON value C<true>, C<false>, C<null>
1643 |  |  |  |  | and numbers. It was deleted and replaced by C<JSON::Boolean>.
1644 |  |  |  |  |
1645 |  |  |  |  | C<JSON::Boolean> represents C<true> and C<false>.
1646 |  |  |  |  |
1647 |  |  |  |  | C<JSON::Boolean> does not represent C<null>.
1648 |  |  |  |  |
1649 |  |  |  |  | C<JSON::null> returns C<undef>.
1650 |  |  |  |  |
1651 |  |  |  |  | C<JSON> makes L<JSON::XS::Boolean> and L<JSON::PP::Boolean> is-a relation
1652 |  |  |  |  | to L<JSON::Boolean>.
1653 |  |  |  |  |
1654 |  |  |  |  | =item function JSON::Number is obsoleted.
1655 |  |  |  |  |
1656 |  |  |  |  | C<JSON::Number> is now needless because JSON::XS and JSON::PP have
1657 |  |  |  |  | round-trip integrity.
1658 |  |  |  |  |
1659 |  |  |  |  | =item JSONRPC modules are deleted.
1660 |  |  |  |  |
1661 |  |  |  |  | Perl implementation of JSON-RPC protocol - C<JSONRPC >, C<JSONRPC::Transport::HTTP>
1662 |  |  |  |  | and C<Apache::JSONRPC > are deleted in this distribution.
1663 |  |  |  |  | Instead of them, there is L<JSON::RPC> which supports JSON-RPC protocol version 1.1.
1664 |  |  |  |  |
1665 |  |  |  |  | =back
1666 |  |  |  |  |
1667 |  |  |  |  | =head2 Transition ways from 1.xx to 2.xx.
1668 |  |  |  |  |
1669 |  |  |  |  | You should set C<suport_by_pp> mode firstly, because
1670 |  |  |  |  | it is always successful for the below codes even with JSON::XS.
1671 |  |  |  |  |
1672 |  |  |  |  | use JSON -support_by_pp;
1673 |  |  |  |  |
1674 |  |  |  |  | =over
1675 |  |  |  |  |
1676 |  |  |  |  | =item Exported jsonToObj (simple)
1677 |  |  |  |  |
1678 |  |  |  |  | from_json($json_text);
1679 |  |  |  |  |
1680 |  |  |  |  | =item Exported objToJson (simple)
1681 |  |  |  |  |
1682 |  |  |  |  | to_json($perl_scalar);
1683 |  |  |  |  |
1684 |  |  |  |  | =item Exported jsonToObj (advanced)
1685 |  |  |  |  |
1686 |  |  |  |  | $flags = {allow_barekey => 1, allow_singlequote => 1};
1687 |  |  |  |  | from_json($json_text, $flags);
1688 |  |  |  |  |
1689 |  |  |  |  | equivalent to:
1690 |  |  |  |  |
1691 |  |  |  |  | $JSON::BareKey = 1;
1692 |  |  |  |  | $JSON::QuotApos = 1;
1693 |  |  |  |  | jsonToObj($json_text);
1694 |  |  |  |  |
1695 |  |  |  |  | =item Exported objToJson (advanced)
1696 |  |  |  |  |
1697 |  |  |  |  | $flags = {allow_blessed => 1, allow_barekey => 1};
1698 |  |  |  |  | to_json($perl_scalar, $flags);
1699 |  |  |  |  |
1700 |  |  |  |  | equivalent to:
1701 |  |  |  |  |
1702 |  |  |  |  | $JSON::BareKey = 1;
1703 |  |  |  |  | objToJson($perl_scalar);
1704 |  |  |  |  |
1705 |  |  |  |  | =item jsonToObj as object method
1706 |  |  |  |  |
1707 |  |  |  |  | $json->decode($json_text);
1708 |  |  |  |  |
1709 |  |  |  |  | =item objToJson as object method
1710 |  |  |  |  |
1711 |  |  |  |  | $json->encode($perl_scalar);
1712 |  |  |  |  |
1713 |  |  |  |  | =item new method with parameters
1714 |  |  |  |  |
1715 |  |  |  |  | The C<new> method in 2.x takes any parameters no longer.
1716 |  |  |  |  | You can set parameters instead;
1717 |  |  |  |  |
1718 |  |  |  |  | $json = JSON->new->pretty;
1719 |  |  |  |  |
1720 |  |  |  |  | =item $JSON::Pretty, $JSON::Indent, $JSON::Delimiter
1721 |  |  |  |  |
1722 |  |  |  |  | If C<indent> is enable, that means C<$JSON::Pretty> flag set. And
1723 |  |  |  |  | C<$JSON::Delimiter> was substituted by C<space_before> and C<space_after>.
1724 |  |  |  |  | In conclusion:
1725 |  |  |  |  |
1726 |  |  |  |  | $json->indent->space_before->space_after;
1727 |  |  |  |  |
1728 |  |  |  |  | Equivalent to:
1729 |  |  |  |  |
1730 |  |  |  |  | $json->pretty;
1731 |  |  |  |  |
1732 |  |  |  |  | To change indent length, use C<indent_length>.
1733 |  |  |  |  |
1734 |  |  |  |  | (Only with JSON::PP, if C<-support_by_pp> is not used.)
1735 |  |  |  |  |
1736 |  |  |  |  | $json->pretty->indent_length(2)->encode($perl_scalar);
1737 |  |  |  |  |
1738 |  |  |  |  | =item $JSON::BareKey
1739 |  |  |  |  |
1740 |  |  |  |  | (Only with JSON::PP, if C<-support_by_pp> is not used.)
1741 |  |  |  |  |
1742 |  |  |  |  | $json->allow_barekey->decode($json_text)
1743 |  |  |  |  |
1744 |  |  |  |  | =item $JSON::ConvBlessed
1745 |  |  |  |  |
1746 |  |  |  |  | use C<-convert_blessed_universally>. See to L<convert_blessed>.
1747 |  |  |  |  |
1748 |  |  |  |  | =item $JSON::QuotApos
1749 |  |  |  |  |
1750 |  |  |  |  | (Only with JSON::PP, if C<-support_by_pp> is not used.)
1751 |  |  |  |  |
1752 |  |  |  |  | $json->allow_singlequote->decode($json_text)
1753 |  |  |  |  |
1754 |  |  |  |  | =item $JSON::SingleQuote
1755 |  |  |  |  |
1756 |  |  |  |  | Disable. C<JSON> does not make such a invalid JSON string any longer.
1757 |  |  |  |  |
1758 |  |  |  |  | =item $JSON::KeySort
1759 |  |  |  |  |
1760 |  |  |  |  | $json->canonical->encode($perl_scalar)
1761 |  |  |  |  |
1762 |  |  |  |  | This is the ascii sort.
1763 |  |  |  |  |
1764 |  |  |  |  | If you want to use with your own sort routine, check the C<sort_by> method.
1765 |  |  |  |  |
1766 |  |  |  |  | (Only with JSON::PP, even if C<-support_by_pp> is used currently.)
1767 |  |  |  |  |
1768 |  |  |  |  | $json->sort_by($sort_routine_ref)->encode($perl_scalar)
1769 |  |  |  |  |
1770 |  |  |  |  | $json->sort_by(sub { $JSON::PP::a <=> $JSON::PP::b })->encode($perl_scalar)
1771 |  |  |  |  |
1772 |  |  |  |  | Can't access C<$a> and C<$b> but C<$JSON::PP::a> and C<$JSON::PP::b>.
1773 |  |  |  |  |
1774 |  |  |  |  | =item $JSON::SkipInvalid
1775 |  |  |  |  |
1776 |  |  |  |  | $json->allow_unknown
1777 |  |  |  |  |
1778 |  |  |  |  | =item $JSON::AUTOCONVERT
1779 |  |  |  |  |
1780 |  |  |  |  | Needless. C<JSON> backend modules have the round-trip integrity.
1781 |  |  |  |  |
1782 |  |  |  |  | =item $JSON::UTF8
1783 |  |  |  |  |
1784 |  |  |  |  | Needless because C<JSON> (JSON::XS/JSON::PP) sets
1785 |  |  |  |  | the UTF8 flag on properly.
1786 |  |  |  |  |
1787 |  |  |  |  | # With UTF8-flagged strings
1788 |  |  |  |  |
1789 |  |  |  |  | $json->allow_nonref;
1790 |  |  |  |  | $str = chr(1000); # UTF8-flagged
1791 |  |  |  |  |
1792 |  |  |  |  | $json_text = $json->utf8(0)->encode($str);
1793 |  |  |  |  | utf8::is_utf8($json_text);
1794 |  |  |  |  | # true
1795 |  |  |  |  | $json_text = $json->utf8(1)->encode($str);
1796 |  |  |  |  | utf8::is_utf8($json_text);
1797 |  |  |  |  | # false
1798 |  |  |  |  |
1799 |  |  |  |  | $str = '"' . chr(1000) . '"'; # UTF8-flagged
1800 |  |  |  |  |
1801 |  |  |  |  | $perl_scalar = $json->utf8(0)->decode($str);
1802 |  |  |  |  | utf8::is_utf8($perl_scalar);
1803 |  |  |  |  | # true
1804 |  |  |  |  | $perl_scalar = $json->utf8(1)->decode($str);
1805 |  |  |  |  | # died because of 'Wide character in subroutine'
1806 |  |  |  |  |
1807 |  |  |  |  | See to L<JSON::XS/A FEW NOTES ON UNICODE AND PERL>.
1808 |  |  |  |  |
1809 |  |  |  |  | =item $JSON::UnMapping
1810 |  |  |  |  |
1811 |  |  |  |  | Disable. See to L<MAPPING>.
1812 |  |  |  |  |
1813 |  |  |  |  | =item $JSON::SelfConvert
1814 |  |  |  |  |
1815 |  |  |  |  | This option was deleted.
1816 |  |  |  |  | Instead of it, if a givien blessed object has the C<TO_JSON> method,
1817 |  |  |  |  | C<TO_JSON> will be executed with C<convert_blessed>.
1818 |  |  |  |  |
1819 |  |  |  |  | $json->convert_blessed->encode($bleesed_hashref_or_arrayref)
1820 |  |  |  |  | # if need, call allow_blessed
1821 |  |  |  |  |
1822 |  |  |  |  | Note that it was C<toJson> in old version, but now not C<toJson> but C<TO_JSON>.
1823 |  |  |  |  |
1824 |  |  |  |  | =back
1825 |  |  |  |  |
1826 |  |  |  |  | =head1 TODO
1827 |  |  |  |  |
1828 |  |  |  |  | =over
1829 |  |  |  |  |
1830 |  |  |  |  | =item example programs
1831 |  |  |  |  |
1832 |  |  |  |  | =back
1833 |  |  |  |  |
1834 |  |  |  |  | =head1 THREADS
1835 |  |  |  |  |
1836 |  |  |  |  | No test with JSON::PP. If with JSON::XS, See to L<JSON::XS/THREADS>.
1837 |  |  |  |  |
1838 |  |  |  |  |
1839 |  |  |  |  | =head1 BUGS
1840 |  |  |  |  |
1841 |  |  |  |  | Please report bugs relevant to C<JSON> to E<lt>makamaka[at]cpan.orgE<gt>.
1842 |  |  |  |  |
1843 |  |  |  |  |
1844 |  |  |  |  | =head1 SEE ALSO
1845 |  |  |  |  |
1846 |  |  |  |  | Most of the document is copied and modified from JSON::XS doc.
1847 |  |  |  |  |
1848 |  |  |  |  | L<JSON::XS>, L<JSON::PP>
1849 |  |  |  |  |
1850 |  |  |  |  | C<RFC4627>(L<http://www.ietf.org/rfc/rfc4627.txt>)
1851 |  |  |  |  |
1852 |  |  |  |  | =head1 AUTHOR
1853 |  |  |  |  |
1854 |  |  |  |  | Makamaka Hannyaharamitu, E<lt>makamaka[at]cpan.orgE<gt>
1855 |  |  |  |  |
1856 |  |  |  |  | JSON::XS was written by Marc Lehmann <schmorp[at]schmorp.de>
1857 |  |  |  |  |
1858 |  |  |  |  | The relese of this new version owes to the courtesy of Marc Lehmann.
1859 |  |  |  |  |
1860 |  |  |  |  |
1861 |  |  |  |  | =head1 COPYRIGHT AND LICENSE
1862 |  |  |  |  |
1863 |  |  |  |  | Copyright 2005-2011 by Makamaka Hannyaharamitu
1864 |  |  |  |  |
1865 |  |  |  |  | This library is free software; you can redistribute it and/or modify
1866 |  |  |  |  | it under the same terms as Perl itself.
1867 |  |  |  |  |
1868 |  |  |  |  | =cut
1869 |  |  |  |  |
1870 |  |  |  |  |
1871 |  |  |  |  | ;