[ViewVC] Diff of: cvs/CBOR-XS/XS.pm

Comparing CBOR-XS/XS.pm (file contents):
Revision 1.14 by root, Tue Oct 29 20:59:16 2013 UTC vs.
Revision 1.21 by root, Wed Nov 20 16:29:02 2013 UTC

…		…
26	substr $many_cbor_strings, 0, $length, ""; # remove decoded cbor string	26	substr $many_cbor_strings, 0, $length, ""; # remove decoded cbor string
27	}	27	}
28		28
29	=head1 DESCRIPTION	29	=head1 DESCRIPTION
30		30
31	WARNING! This module is very new, and not very well tested (that's up to	31	WARNING! This module is very new, and not very well tested (that's up
32	you to do). Furthermore, details of the implementation might change freely	32	to you to do). Furthermore, details of the implementation might change
33	before version 1.0. And lastly, the object serialisation protocol depends	33	freely before version 1.0. And lastly, most extensions depend on an IANA
34	on a pending IANA assignment, and until that assignment is official, this	34	assignment, and until that assignment is official, this implementation is
35	implementation is not interoperable with other implementations (even	35	not interoperable with other implementations (even future versions of this
36	future versions of this module) until the assignment is done.	36	module) until the assignment is done.
37		37
38	You are still invited to try out CBOR, and this module.	38	You are still invited to try out CBOR, and this module.
39		39
40	This module converts Perl data structures to the Concise Binary Object	40	This module converts Perl data structures to the Concise Binary Object
41	Representation (CBOR) and vice versa. CBOR is a fast binary serialisation	41	Representation (CBOR) and vice versa. CBOR is a fast binary serialisation
…		…
46	In short, CBOR is a faster and very compact binary alternative to JSON,	46	In short, CBOR is a faster and very compact binary alternative to JSON,
47	with the added ability of supporting serialisation of Perl objects. (JSON	47	with the added ability of supporting serialisation of Perl objects. (JSON
48	often compresses better than CBOR though, so if you plan to compress the	48	often compresses better than CBOR though, so if you plan to compress the
49	data later you might want to compare both formats first).	49	data later you might want to compare both formats first).
50		50
51	To give you a general idea, with texts in the megabyte range, C<CBOR::XS>	51	To give you a general idea about speed, with texts in the megabyte range,
52	usually encodes roughly twice as fast as L<Storable> or L<JSON::XS> and	52	C<CBOR::XS> usually encodes roughly twice as fast as L<Storable> or
53	decodes about 15%-30% faster than those. The shorter the data, the worse	53	L<JSON::XS> and decodes about 15%-30% faster than those. The shorter the
54	L<Storable> performs in comparison.	54	data, the worse L<Storable> performs in comparison.
		55
		56	As for compactness, C<CBOR::XS> encoded data structures are usually about
		57	20% smaller than the same data encoded as (compact) JSON or L<Storable>.
		58
		59	In addition to the core CBOR data format, this module implements a number
		60	of extensions, to support cyclic and self-referencing data structures
		61	(see C<allow_sharing>), string deduplication (see C<allow_stringref>) and
		62	scalar references (always enabled).
55		63
56	The primary goal of this module is to be I<correct> and the secondary goal	64	The primary goal of this module is to be I<correct> and the secondary goal
57	is to be I<fast>. To reach the latter goal it was written in C.	65	is to be I<fast>. To reach the latter goal it was written in C.
58		66
59	See MAPPING, below, on how CBOR::XS maps perl values to CBOR values and	67	See MAPPING, below, on how CBOR::XS maps perl values to CBOR values and
…		…
63		71
64	package CBOR::XS;	72	package CBOR::XS;
65		73
66	use common::sense;	74	use common::sense;
67		75
68	our $VERSION = 0.06;	76	our $VERSION = 0.08;
69	our @ISA = qw(Exporter);	77	our @ISA = qw(Exporter);
70		78
71	our @EXPORT = qw(encode_cbor decode_cbor);	79	our @EXPORT = qw(encode_cbor decode_cbor);
72		80
73	use Exporter;	81	use Exporter;
…		…
153		161
154	If no argument is given, the limit check will be deactivated (same as when	162	If no argument is given, the limit check will be deactivated (same as when
155	C<0> is specified).	163	C<0> is specified).
156		164
157	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.	165	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.
		166
		167	=item $cbor = $cbor->allow_unknown ([$enable])
		168
		169	=item $enabled = $cbor->get_allow_unknown
		170
		171	If C<$enable> is true (or missing), then C<encode> will I<not> throw an
		172	exception when it encounters values it cannot represent in CBOR (for
		173	example, filehandles) but instead will encode a CBOR C<error> value.
		174
		175	If C<$enable> is false (the default), then C<encode> will throw an
		176	exception when it encounters anything it cannot encode as CBOR.
		177
		178	This option does not affect C<decode> in any way, and it is recommended to
		179	leave it off unless you know your communications partner.
		180
		181	=item $cbor = $cbor->allow_sharing ([$enable])
		182
		183	=item $enabled = $cbor->get_allow_sharing
		184
		185	If C<$enable> is true (or missing), then C<encode> will not double-encode
		186	values that have been referenced before (e.g. when the same object, such
		187	as an array, is referenced multiple times), but instead will emit a
		188	reference to the earlier value.
		189
		190	This means that such values will only be encoded once, and will not result
		191	in a deep cloning of the value on decode, in decoders supporting the value
		192	sharing extension.
		193
		194	It is recommended to leave it off unless you know your
		195	communication partner supports the value sharing extensions to CBOR
		196	(http://cbor.schmorp.de/value-sharing).
		197
		198	Detecting shared values incurs a runtime overhead when values are encoded
		199	that have a reference counter large than one, and might unnecessarily
		200	increase the encoded size, as potentially shared values are encode as
		201	sharable whether or not they are actually shared.
		202
		203	At the moment, only targets of references can be shared (e.g. scalars,
		204	arrays or hashes pointed to by a reference). Weirder constructs, such as
		205	an array with multiple "copies" of the I<same> string, which are hard but
		206	not impossible to create in Perl, are not supported (this is the same as
		207	for L<Storable>).
		208
		209	If C<$enable> is false (the default), then C<encode> will encode
		210	exception when it encounters anything it cannot encode as CBOR.
		211
		212	This option does not affect C<decode> in any way - shared values and
		213	references will always be decoded properly if present.
		214
		215	=item $cbor = $cbor->allow_stringref ([$enable])
		216
		217	=item $enabled = $cbor->get_allow_stringref
		218
		219	If C<$enable> is true (or missing), then C<encode> will try not to encode
		220	the same string twice, but will instead encode a reference to the string
		221	instead. Depending on your data format. this can save a lot of space, but
		222	also results in a very large runtime overhead (expect encoding times to be
		223	2-4 times as high as without).
		224
		225	It is recommended to leave it off unless you know your
		226	communications partner supports the stringref extension to CBOR
		227	(http://cbor.schmorp.de/stringref).
		228
		229	If C<$enable> is false (the default), then C<encode> will encode
		230	exception when it encounters anything it cannot encode as CBOR.
		231
		232	This option does not affect C<decode> in any way - string references will
		233	always be decoded properly if present.
158		234
159	=item $cbor_data = $cbor->encode ($perl_scalar)	235	=item $cbor_data = $cbor->encode ($perl_scalar)
160		236
161	Converts the given Perl data structure (a scalar value) to its CBOR	237	Converts the given Perl data structure (a scalar value) to its CBOR
162	representation.	238	representation.
…		…
452	=head1 MAGIC HEADER	528	=head1 MAGIC HEADER
453		529
454	There is no way to distinguish CBOR from other formats	530	There is no way to distinguish CBOR from other formats
455	programmatically. To make it easier to distinguish CBOR from other	531	programmatically. To make it easier to distinguish CBOR from other
456	formats, the CBOR specification has a special "magic string" that can be	532	formats, the CBOR specification has a special "magic string" that can be
457	prepended to any CBOR string without changing it's meaning.	533	prepended to any CBOR string without changing its meaning.
458		534
459	This string is available as C<$CBOR::XS::MAGIC>. This module does not	535	This string is available as C<$CBOR::XS::MAGIC>. This module does not
460	prepend this string tot he CBOR data it generates, but it will ignroe it	536	prepend this string to the CBOR data it generates, but it will ignore it
461	if present, so users can prepend this string as a "file type" indicator as	537	if present, so users can prepend this string as a "file type" indicator as
462	required.	538	required.
463		539
464		540
465	=head1 THE CBOR::XS::Tagged CLASS	541	=head1 THE CBOR::XS::Tagged CLASS
…		…
548	Wrap CBOR data in CBOR:	624	Wrap CBOR data in CBOR:
549		625
550	my $cbor_cbor = encode_cbor	626	my $cbor_cbor = encode_cbor
551	CBOR::XS::tag 24,	627	CBOR::XS::tag 24,
552	encode_cbor [1, 2, 3];	628	encode_cbor [1, 2, 3];
		629
		630	=head1 TAG HANDLING AND EXTENSIONS
		631
		632	This section describes how this module handles specific tagged values and
		633	extensions. If a tag is not mentioned here, then the default handling
		634	applies (creating a CBOR::XS::Tagged object on decoding, and only encoding
		635	the tag when explicitly requested).
		636
		637	Future versions of this module reserve the right to special case
		638	additional tags (such as bigfloat or base64url).
		639
		640	=over 4
		641
		642	=item <unassigned> (perl-object, L<http://cbor.schmorp.de/perl-object>)
		643
		644	These tags are automatically created for serialisable objects using the
		645	C<FREEZE/THAW> methods (the L<Types::Serialier> object serialisation
		646	protocol).
		647
		648	=item <unassigned>, <unassigned> (sharable, sharedref, L <http://cbor.schmorp.de/value-sharing>)
		649
		650	These tags are automatically decoded when encountered, resulting in
		651	shared values in the decoded object. They are only encoded, however, when
		652	C<allow_sharable> is enabled.
		653
		654	=item <unassigned>, <unassigned> (stringref-namespace, stringref, L <http://cbor.schmorp.de/stringref>)
		655
		656	These tags are automatically decoded when encountered. They are only
		657	encoded, however, when C<allow_stringref> is enabled.
		658
		659	=item 22098 (indirection, L<http://cbor.schmorp.de/indirection>)
		660
		661	This tag is automatically generated when a reference are encountered (with
		662	the exception of hash and array refernces). It is converted to a reference
		663	when decoding.
		664
		665	=item 55799 (self-describe CBOR, RFC 7049)
		666
		667	This value is not generated on encoding (unless explicitly requested by
		668	the user), and is simply ignored when decoding.
		669
		670	=back
		671
553		672
554	=head1 CBOR and JSON	673	=head1 CBOR and JSON
555		674
556	CBOR is supposed to implement a superset of the JSON data model, and is,	675	CBOR is supposed to implement a superset of the JSON data model, and is,
557	with some coercion, able to represent all JSON texts (something that other	676	with some coercion, able to represent all JSON texts (something that other

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Comparing CBOR-XS/XS.pm (file contents): Revision 1.14 by root, Tue Oct 29 20:59:16 2013 UTC vs. Revision 1.21 by root, Wed Nov 20 16:29:02 2013 UTC

Diff Legend

Comparing CBOR-XS/XS.pm (file contents):
Revision 1.14 by root, Tue Oct 29 20:59:16 2013 UTC vs.
Revision 1.21 by root, Wed Nov 20 16:29:02 2013 UTC