[ViewVC] Diff of: cvs/JSON-XS/README

Comparing JSON-XS/README (file contents):
Revision 1.19 by root, Sat Oct 13 01:57:46 2007 UTC vs.
Revision 1.21 by root, Tue Dec 4 10:37:42 2007 UTC

      # OO-interface
      $coder = JSON::XS->new->ascii->pretty->allow_nonref;
      $pretty_printed_unencoded = $coder->encode ($perl_scalar);
      $perl_scalar = $coder->decode ($unicode_json_text);
+     # Note that JSON version 2.0 and above will automatically use JSON::XS
+     # if available, at virtually no speed overhead either, so you should
+     # be able to just:
+     use JSON;
+     # and do the same things, except that you have a pure-perl fallback now.
 DESCRIPTION
     This module converts Perl data structures to JSON and vice versa. Its
     primary goal is to be *correct* and its secondary goal is to be *fast*.
     To reach the latter goal it was written in C.
+    Beginning with version 2.0 of the JSON module, when both JSON and
+    JSON::XS are installed, then JSON will fall back on JSON::XS (this can
+    be overriden) with no overhead due to emulation (by inheritign
+    constructor and methods). If JSON::XS is not available, it will fall
+    back to the compatible JSON::PP module as backend, so using JSON instead
+    of JSON::XS gives you a portable JSON API that can be fast when you need
+    and doesn't require a C compiler when that is a problem.
     As this is the n-th-something JSON module on CPAN, what was the reason
     to write yet another JSON module? While it seems there are many JSON
     modules, none of them correctly handle all corner cases, and in most
     cases their maintainers are unresponsive, gone missing, or not listening
     See MAPPING, below, on how JSON::XS maps perl values to JSON values and
     vice versa.
   FEATURES
-    * correct unicode handling
+    * correct Unicode handling
         This module knows how to handle Unicode, and even documents how and
         when it does so.
     * round-trip integrity
         When you serialise a perl data structure using only datatypes
     * simple to use
         This module has both a simple functional interface as well as an OO
         interface.
     * reasonably versatile output formats
-        You can choose between the most compact guarenteed single-line
+        You can choose between the most compact guaranteed single-line
         format possible (nice for simple line-based protocols), a pure-ascii
         format (for when your transport is not 8-bit clean, still supports
-        the whole unicode range), or a pretty-printed format (for when you
+        the whole Unicode range), or a pretty-printed format (for when you
         want to read that stuff). Or you can combine those features in
         whatever way you like.
 FUNCTIONAL INTERFACE
-    The following convinience methods are provided by this module. They are
+    The following convenience methods are provided by this module. They are
     exported by default:
     $json_text = to_json $perl_scalar
         Converts the given Perl data structure to a UTF-8 encoded, binary
         string (that is, the string contains octets only). Croaks on error.
 A FEW NOTES ON UNICODE AND PERL
     Since this often leads to confusion, here are a few very clear words on
     how Unicode works in Perl, modulo bugs.
     1. Perl strings can store characters with ordinal values > 255.
-        This enables you to store unicode characters as single characters in
+        This enables you to store Unicode characters as single characters in
         a Perl string - very natural.
     2. Perl does *not* associate an encoding with your strings.
         Unless you force it to, e.g. when matching it against a regex, or
         printing the scalar to a file, in which case Perl either interprets
     3. The internal utf-8 flag has no meaning with regards to the encoding
     of your string.
         Just ignore that flag unless you debug a Perl bug, a module written
         in XS or want to dive into the internals of perl. Otherwise it will
         only confuse you, as, despite the name, it says nothing about how
-        your string is encoded. You can have unicode strings with that flag
+        your string is encoded. You can have Unicode strings with that flag
         set, with that flag clear, and you can have binary data with that
         flag set and that flag clear. Other possibilities exist, too.
         If you didn't know about that flag, just the better, pretend it
         doesn't exist.
         If you have UTF-8 encoded data, it is no longer a Unicode string,
         but a Unicode string encoded in UTF-8, giving you a binary string.
     5. A string containing "high" (> 255) character values is *not* a UTF-8
     string.
-        Its a fact. Learn to live with it.
+        It's a fact. Learn to live with it.
     I hope this helps :)
 OBJECT-ORIENTED INTERFACE
     The object oriented interface lets you configure your own encoding or
            my $json = JSON::XS->new->utf8->space_after->encode ({a => [1,2]})
            => {"a": [1, 2]}
     $json = $json->ascii ([$enable])
+    $enabled = $json->get_ascii
         If $enable is true (or missing), then the "encode" method will not
         generate characters outside the code range 0..127 (which is ASCII).
-        Any unicode characters outside that range will be escaped using
+        Any Unicode characters outside that range will be escaped using
         either a single \uXXXX (BMP characters) or a double \uHHHH\uLLLLL
         escape sequence, as per RFC4627. The resulting encoded JSON text can
-        be treated as a native unicode string, an ascii-encoded,
+        be treated as a native Unicode string, an ascii-encoded,
         latin1-encoded or UTF-8 encoded string, or any other superset of
         ASCII.
         If $enable is false, then the "encode" method will not escape
         Unicode characters unless required by the JSON syntax or other
           JSON::XS->new->ascii (1)->encode ([chr 0x10401])
           => ["\ud801\udc01"]
     $json = $json->latin1 ([$enable])
+    $enabled = $json->get_latin1
         If $enable is true (or missing), then the "encode" method will
         encode the resulting JSON text as latin1 (or iso-8859-1), escaping
         any characters outside the code range 0..255. The resulting string
-        can be treated as a latin1-encoded JSON text or a native unicode
+        can be treated as a latin1-encoded JSON text or a native Unicode
         string. The "decode" method will not be affected in any way by this
-        flag, as "decode" by default expects unicode, which is a strict
+        flag, as "decode" by default expects Unicode, which is a strict
         superset of latin1.
         If $enable is false, then the "encode" method will not escape
         Unicode characters unless required by the JSON syntax or other
         flags.
         The main use for this flag is efficiently encoding binary data as
         JSON text, as most octets will not be escaped, resulting in a
         smaller encoded size. The disadvantage is that the resulting JSON
         text is encoded in latin1 (and must correctly be treated as such
-        when storing and transfering), a rare encoding for JSON. It is
+        when storing and transferring), a rare encoding for JSON. It is
         therefore most useful when you want to store data structures known
         to contain binary data efficiently in files or databases, not when
         talking to other JSON encoders/decoders.
           JSON::XS->new->latin1->encode (["\x{89}\x{abc}"]
           => ["\x{89}\\u0abc"]    # (perl syntax, U+abc escaped, U+89 not)
     $json = $json->utf8 ([$enable])
+    $enabled = $json->get_utf8
         If $enable is true (or missing), then the "encode" method will
         encode the JSON result into UTF-8, as required by many protocols,
         while the "decode" method expects to be handled an UTF-8-encoded
         string. Please note that UTF-8-encoded strings do not contain any
         characters outside the range 0..255, they are thus useful for
         bytewise/binary I/O. In future versions, enabling this option might
         enable autodetection of the UTF-16 and UTF-32 encoding families, as
         described in RFC4627.
         If $enable is false, then the "encode" method will return the JSON
-        string as a (non-encoded) unicode string, while "decode" expects
+        string as a (non-encoded) Unicode string, while "decode" expects
-        thus a unicode string. Any decoding or encoding (e.g. to UTF-8 or
+        thus a Unicode string. Any decoding or encoding (e.g. to UTF-8 or
         UTF-16) needs to be done yourself, e.g. using the Encode module.
         Example, output UTF-16BE-encoded JSON:
           use Encode;
                  2
               ]
            }
     $json = $json->indent ([$enable])
+    $enabled = $json->get_indent
         If $enable is true (or missing), then the "encode" method will use a
         multiline format as output, putting every array member or
-        object/hash key-value pair into its own line, identing them
+        object/hash key-value pair into its own line, indenting them
         properly.
         If $enable is false, no newlines or indenting will be produced, and
-        the resulting JSON text is guarenteed not to contain any "newlines".
+        the resulting JSON text is guaranteed not to contain any "newlines".
         This setting has no effect when decoding JSON texts.
     $json = $json->space_before ([$enable])
+    $enabled = $json->get_space_before
         If $enable is true (or missing), then the "encode" method will add
         an extra optional space before the ":" separating keys from values
         in JSON objects.
         If $enable is false, then the "encode" method will not add any extra
         Example, space_before enabled, space_after and indent disabled:
            {"key" :"value"}
     $json = $json->space_after ([$enable])
+    $enabled = $json->get_space_after
         If $enable is true (or missing), then the "encode" method will add
         an extra optional space after the ":" separating keys from values in
         JSON objects and extra whitespace after the "," separating key-value
         pairs and array members.
         Example, space_before and indent disabled, space_after enabled:
            {"key": "value"}
     $json = $json->relaxed ([$enable])
+    $enabled = $json->get_relaxed
         If $enable is true (or missing), then "decode" will accept some
         extensions to normal JSON syntax (see below). "encode" will not be
         affected in anyway. *Be aware that this option makes you accept
         invalid JSON texts as if they were valid!*. I suggest only to use
         this option to parse application-specific files written by humans
                  1, # this comment not allowed in JSON
                     # neither this one...
               ]
     $json = $json->canonical ([$enable])
+    $enabled = $json->get_canonical
         If $enable is true (or missing), then the "encode" method will
         output JSON objects by sorting their keys. This is adding a
         comparatively high overhead.
         If $enable is false, then the "encode" method will output key-value
         pairs in the order Perl stores them (which will likely change
         between runs of the same script).
         This option is useful if you want the same data structure to be
         encoded as the same JSON text (given the same overall settings). If
-        it is disabled, the same hash migh be encoded differently even if
+        it is disabled, the same hash might be encoded differently even if
         contains the same data, as key-value pairs have no inherent ordering
         in Perl.
         This setting has no effect when decoding JSON texts.
     $json = $json->allow_nonref ([$enable])
+    $enabled = $json->get_allow_nonref
         If $enable is true (or missing), then the "encode" method can
         convert a non-reference into its corresponding string, number or
         null JSON value, which is an extension to RFC4627. Likewise,
         "decode" will accept those JSON values instead of croaking.
            JSON::XS->new->allow_nonref->encode ("Hello, World!")
            => "Hello, World!"
     $json = $json->allow_blessed ([$enable])
+    $enabled = $json->get_allow_blessed
         If $enable is true (or missing), then the "encode" method will not
         barf when it encounters a blessed reference. Instead, the value of
-        the convert_blessed option will decide wether "null"
+        the convert_blessed option will decide whether "null"
-        ("convert_blessed" disabled or no "to_json" method found) or a
+        ("convert_blessed" disabled or no "TO_JSON" method found) or a
         representation of the object ("convert_blessed" enabled and
-        "to_json" method found) is being encoded. Has no effect on "decode".
+        "TO_JSON" method found) is being encoded. Has no effect on "decode".
         If $enable is false (the default), then "encode" will throw an
         exception when it encounters a blessed object.
     $json = $json->convert_blessed ([$enable])
+    $enabled = $json->get_convert_blessed
         If $enable is true (or missing), then "encode", upon encountering a
         blessed object, will check for the availability of the "TO_JSON"
         method on the object's class. If found, it will be called in scalar
         context and the resulting scalar will be encoded instead of the
         object. If no "TO_JSON" method is found, the value of
         As this callback gets called less often then the
         "filter_json_object" one, decoding speed will not usually suffer as
         much. Therefore, single-key objects make excellent targets to
         serialise Perl objects into, especially as single-key JSON objects
-        are as close to the type-tagged value concept as JSON gets (its
+        are as close to the type-tagged value concept as JSON gets (it's
         basically an ID/VALUE tuple). Of course, JSON does not support this
         in any way, so you need to make sure your data never looks like a
         serialised Perl hash.
         Typical names for the single object key are "__class_whatever__", or
               { __widget__ => $self->{id} }
            }
     $json = $json->shrink ([$enable])
+    $enabled = $json->get_shrink
         Perl usually over-allocates memory a bit when allocating space for
         strings. This flag optionally resizes strings generated by either
         "encode" or "decode" to their minimum size possible. This can save
         memory when your JSON texts are either very very long or you have
         many short strings. It will also try to downgrade any strings to
         converting strings that look like integers or floats into integers
         or floats internally (there is no difference on the Perl level),
         saving space.
     $json = $json->max_depth ([$maximum_nesting_depth])
+    $max_depth = $json->get_max_depth
         Sets the maximum nesting level (default 512) accepted while encoding
         or decoding. If the JSON text or Perl data structure has an equal or
         higher nesting level then this limit, then the encoder and decoder
         will stop and croak at that point.
         See SECURITY CONSIDERATIONS, below, for more info on why this is
         useful.
     $json = $json->max_size ([$maximum_string_size])
+    $max_size = $json->get_max_size
         Set the maximum length a JSON text may have (in bytes) where
         decoding is being attempted. The default is 0, meaning no limit.
         When "decode" is called on a string longer then this number of
         characters it will not attempt to decode the string but throw an
         exception. This setting has no effect on "encode" (yet).
     vice versa. These mappings are designed to "do the right thing" in most
     circumstances automatically, preserving round-tripping characteristics
     (what you put in comes out as something equivalent).
     For the more enlightened: note that in the following descriptions,
-    lowercase *perl* refers to the Perl interpreter, while uppcercase *Perl*
+    lowercase *perl* refers to the Perl interpreter, while uppercase *Perl*
     refers to the abstract Perl language itself.
   JSON -> PERL
     object
         A JSON object becomes a reference to a hash in Perl. No ordering of
-        object keys is preserved (JSON does not preserver object key
+        object keys is preserved (JSON does not preserve object key ordering
-        ordering itself).
+        itself).
     array
         A JSON array becomes a reference to an array in Perl.
     string
         strings, but as Perl is typeless there is no other way to do it.
     true, false
         These JSON atoms become "JSON::XS::true" and "JSON::XS::false",
         respectively. They are overloaded to act almost exactly like the
-        numbers 1 and 0. You can check wether a scalar is a JSON boolean by
+        numbers 1 and 0. You can check whether a scalar is a JSON boolean by
         using the "JSON::XS::is_bool" function.
     null
         A JSON null atom becomes "undef" in Perl.
            to_json [$value]                 # yields ["5"]
            # undef becomes null
            to_json [undef]                  # yields [null]
-        You can force the type to be a string by stringifying it:
+        You can force the type to be a JSON string by stringifying it:
            my $x = 3.1; # some variable containing a number
            "$x";        # stringified
            $x .= "";    # another, more awkward way to stringify
            print $x;    # perl does it for you, too, quite often
-        You can force the type to be a number by numifying it:
+        You can force the type to be a JSON number by numifying it:
            my $x = "3"; # some variable containing a string
            $x += 0;     # numify it, ensuring it will be dumped as a number
-           $x *= 1;     # same thing, the choise is yours.
+           $x *= 1;     # same thing, the choice is yours.
-        You can not currently output JSON booleans or force the type in
+        You can not currently force the type in other, less obscure, ways.
-        other, less obscure, ways. Tell me if you need this capability.
+        Tell me if you need this capability.
 COMPARISON
     As already mentioned, this module was created because none of the
     existing JSON modules could be made to work correctly. First I will
     describe the problems (or pleasures) I encountered with various existing
     not to suffer from any of these problems or limitations.
     JSON 1.07
         Slow (but very portable, as it is written in pure Perl).
-        Undocumented/buggy Unicode handling (how JSON handles unicode values
+        Undocumented/buggy Unicode handling (how JSON handles Unicode values
-        is undocumented. One can get far by feeding it unicode strings and
+        is undocumented. One can get far by feeding it Unicode strings and
-        doing en-/decoding oneself, but unicode escapes are not working
+        doing en-/decoding oneself, but Unicode escapes are not working
         properly).
-        No roundtripping (strings get clobbered if they look like numbers,
+        No round-tripping (strings get clobbered if they look like numbers,
         e.g. the string 2.0 will encode to 2.0 instead of "2.0", and that
         will decode into the number 2.
     JSON::PC 0.01
         Very fast.
         Undocumented/buggy Unicode handling.
-        No roundtripping.
+        No round-tripping.
         Has problems handling many Perl values (e.g. regex results and other
         magic values will make it croak).
         Does not even generate valid JSON ("{1,2}" gets converted to "{1:2}"
         much undocumented. I need at least a format for easy reading by
         humans and a single-line compact format for use in a protocol, and
         preferably a way to generate ASCII-only JSON texts).
         Completely broken (and confusingly documented) Unicode handling
-        (unicode escapes are not working properly, you need to set
+        (Unicode escapes are not working properly, you need to set
         ImplicitUnicode to *different* values on en- and decoding to get
         symmetric behaviour).
-        No roundtripping (simple cases work, but this depends on wether the
+        No round-tripping (simple cases work, but this depends on whether
-        scalar value was used in a numeric context or not).
+        the scalar value was used in a numeric context or not).
         Dumping hashes may skip hash values depending on iterator state.
         Unmaintained (maintainer unresponsive for many months, bugs are not
         getting fixed).
         Does not check input for validity (i.e. will accept non-JSON input
         and return "something" instead of raising an exception. This is a
-        security issue: imagine two banks transfering money between each
+        security issue: imagine two banks transferring money between each
         other using JSON. One bank might parse a given non-JSON request and
         deduct money, while the other might reject the transaction with a
         syntax error. While a good protocol will at least recover, that is
         extra unnecessary work and the transaction will still not succeed).
     JSON::DWIW 0.04
         Very fast. Very natural. Very nice.
-        Undocumented unicode handling (but the best of the pack. Unicode
+        Undocumented Unicode handling (but the best of the pack. Unicode
         escapes still don't get parsed properly).
         Very inflexible.
-        No roundtripping.
+        No round-tripping.
         Does not generate valid JSON texts (key strings are often unquoted,
         empty keys result in nothing being output)
         Does not check input for validity.
        my $yaml = $to_yaml->encode ($ref) . "\n";
     This will usually generate JSON texts that also parse as valid YAML.
     Please note that YAML has hardcoded limits on (simple) object key
     lengths that JSON doesn't have, so you should make sure that your hash
-    keys are noticably shorter than the 1024 characters YAML allows.
+    keys are noticeably shorter than the 1024 characters YAML allows.
     There might be other incompatibilities that I am not aware of. In
     general you should not try to generate YAML with a JSON generator or
     vice versa, or try to parse JSON with a YAML parser or vice versa:
     chances are high that you will run into severe interoperability
     It shows the number of encodes/decodes per second (JSON::XS uses the
     functional interface, while JSON::XS/2 uses the OO interface with
     pretty-printing and hashkey sorting enabled, JSON::XS/3 enables shrink).
     Higher is better:
-       Storable   |  15779.925 |  14169.946 |
-       -----------+------------+------------+
        module     |     encode |     decode |
        -----------|------------|------------|
-       JSON       |   4990.842 |   4088.813 |
+       JSON 1.x   |   4990.842 |   4088.813 |
        JSON::DWIW |  51653.990 |  71575.154 |
        JSON::PC   |  65948.176 |  74631.744 |
        JSON::PP   |   8931.652 |   3817.168 |
        JSON::Syck |  24877.248 |  27776.848 |
        JSON::XS   | 388361.481 | 227951.304 |
        JSON::XS/3 | 338250.323 | 218453.333 |
        Storable   |  16500.016 | 135300.129 |
        -----------+------------+------------+
     That is, JSON::XS is about five times faster than JSON::DWIW on
-    encoding, about three times faster on decoding, and over fourty times
+    encoding, about three times faster on decoding, and over forty times
     faster than JSON, even with pretty-printing and key sorting. It also
     compares favourably to Storable for small amounts of data.
     Using a longer test string (roughly 18KB, generated from Yahoo! Locals
     search API (http://nanoref.com/yahooapis/mgPdGg):
        module     |     encode |     decode |
        -----------|------------|------------|
-       JSON       |     55.260 |     34.971 |
+       JSON 1.x   |     55.260 |     34.971 |
        JSON::DWIW |    825.228 |   1082.513 |
        JSON::PC   |   3571.444 |   2394.829 |
        JSON::PP   |    210.987 |     32.574 |
        JSON::Syck |    552.551 |    787.544 |
        JSON::XS   |   5780.463 |   4854.519 |
        -----------+------------+------------+
     Again, JSON::XS leads by far (except for Storable which non-surprisingly
     decodes faster).
-    On large strings containing lots of high unicode characters, some
+    On large strings containing lots of high Unicode characters, some
     modules (such as JSON::PC) seem to decode faster than JSON::XS, but the
-    result will be broken due to missing (or wrong) unicode handling. Others
+    result will be broken due to missing (or wrong) Unicode handling. Others
     refuse to decode or encode properly, so it was impossible to prepare a
     fair comparison table for that case.
 SECURITY CONSIDERATIONS
     When you are using JSON in a protocol, talking to untrusted potentially
     have any buffer overflows. Obviously, this module should ensure that and
     I am trying hard on making that true, but you never know.
     Second, you need to avoid resource-starving attacks. That means you
     should limit the size of JSON texts you accept, or make sure then when
-    your resources run out, thats just fine (e.g. by using a separate
+    your resources run out, that's just fine (e.g. by using a separate
     process that can crash safely). The size of a JSON text in octets or
     characters is usually a good indication of the size of the resources
     required to decode it into a Perl structure. While JSON::XS can check
     the size of the JSON text, it might be too late when you already have it
     in memory, so you might want to check the size before you accept the
     And last but least, something else could bomb you that I forgot to think
     of. In that case, you get to keep the pieces. I am always open for
     hints, though...
-    If you are using JSON::XS to return packets to consumption by javascript
+    If you are using JSON::XS to return packets to consumption by JavaScript
     scripts in a browser you should have a look at
-    <http://jpsykes.com/47/practical-csrf-and-json-security> to see wether
+    <http://jpsykes.com/47/practical-csrf-and-json-security> to see whether
     you are vulnerable to some common attack vectors (which really are
     browser design bugs, but it is still you who will have to deal with it,
     as major browser developers care only for features, not about doing
     security right).
 THREADS
-    This module is *not* guarenteed to be thread safe and there are no plans
+    This module is *not* guaranteed to be thread safe and there are no plans
     to change this until Perl gets thread support (as opposed to the
     horribly slow so-called "threads" which are simply slow and bloated
     process simulations - use fork, its *much* faster, cheaper, better).
-    (It might actually work, but you ahve ben warned).
+    (It might actually work, but you have been warned).
 BUGS
     While the goal of this module is to be correct, that unfortunately does
     not mean its bug-free, only that I think its design is bug-free. It is
     still relatively early in its development. If you keep reporting bugs

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Comparing JSON-XS/README (file contents): Revision 1.19 by root, Sat Oct 13 01:57:46 2007 UTC vs. Revision 1.21 by root, Tue Dec 4 10:37:42 2007 UTC

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Comparing JSON-XS/README (file contents):
Revision 1.19 by root, Sat Oct 13 01:57:46 2007 UTC vs.
Revision 1.21 by root, Tue Dec 4 10:37:42 2007 UTC