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diff --git a/ext/json/lib/json.rb b/ext/json/lib/json.rb
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require 'json/common'
-# = json - JSON for Ruby
-#
-# == Description
-#
-# This is a implementation of the JSON specification according to RFC 4627
-# (http://www.ietf.org/rfc/rfc4627.txt). Starting from version 1.0.0 on there
-# will be two variants available:
-#
-# * A pure ruby variant, that relies on the iconv and the stringscan
-# extensions, which are both part of the ruby standard library.
-# * The quite a bit faster C extension variant, which is in parts implemented
-# in C and comes with its own unicode conversion functions and a parser
-# generated by the ragel state machine compiler
-# (http://www.cs.queensu.ca/~thurston/ragel).
-#
-# Both variants of the JSON generator escape all non-ASCII an control
-# characters with \uXXXX escape sequences, and support UTF-16 surrogate pairs
-# in order to be able to generate the whole range of unicode code points. This
-# means that generated JSON text is encoded as UTF-8 (because ASCII is a subset
-# of UTF-8) and at the same time avoids decoding problems for receiving
-# endpoints, that don't expect UTF-8 encoded texts. On the negative side this
-# may lead to a bit longer strings than necessarry.
-#
-# All strings, that are to be encoded as JSON strings, should be UTF-8 byte
-# sequences on the Ruby side. To encode raw binary strings, that aren't UTF-8
-# encoded, please use the to_json_raw_object method of String (which produces
-# an object, that contains a byte array) and decode the result on the receiving
-# endpoint.
-#
-# == Author
-#
-# Florian Frank <mailto:flori@ping.de>
-#
-# == License
-#
-# This software is distributed under the same license as Ruby itself, see
-# http://www.ruby-lang.org/en/LICENSE.txt.
-#
-# == Download
-#
-# The latest version of this library can be downloaded at
-#
-# * http://rubyforge.org/frs?group_id=953
-#
-# Online Documentation should be located at
-#
-# * http://json.rubyforge.org
-#
-# == Usage
-#
-# To use JSON you can
-# require 'json'
-# to load the installed variant (either the extension 'json' or the pure
-# variant 'json_pure'). If you have installed the extension variant, you can
-# pick either the extension variant or the pure variant by typing
-# require 'json/ext'
-# or
-# require 'json/pure'
-#
-# You can choose to load a set of common additions to ruby core's objects if
-# you
-# require 'json/add/core'
-#
-# After requiring this you can, e. g., serialise/deserialise Ruby ranges:
-#
-# JSON JSON(1..10) # => 1..10
-#
-# To find out how to add JSON support to other or your own classes, read the
-# Examples section below.
-#
-# To get the best compatibility to rails' JSON implementation, you can
-# require 'json/add/rails'
-#
-# Both of the additions attempt to require 'json' (like above) first, if it has
-# not been required yet.
-#
-# == Speed Comparisons
-#
-# I have created some benchmark results (see the benchmarks/data-p4-3Ghz
-# subdir of the package) for the JSON-parser to estimate the speed up in the C
-# extension:
-#
-# Comparing times (call_time_mean):
-# 1 ParserBenchmarkExt#parser 900 repeats:
-# 553.922304770 ( real) -> 21.500x
-# 0.001805307
-# 2 ParserBenchmarkYAML#parser 1000 repeats:
-# 224.513358139 ( real) -> 8.714x
-# 0.004454078
-# 3 ParserBenchmarkPure#parser 1000 repeats:
-# 26.755020642 ( real) -> 1.038x
-# 0.037376163
-# 4 ParserBenchmarkRails#parser 1000 repeats:
-# 25.763381731 ( real) -> 1.000x
-# 0.038814780
-# calls/sec ( time) -> speed covers
-# secs/call
-#
-# In the table above 1 is JSON::Ext::Parser, 2 is YAML.load with YAML
-# compatbile JSON document, 3 is is JSON::Pure::Parser, and 4 is
-# ActiveSupport::JSON.decode. The ActiveSupport JSON-decoder converts the
-# input first to YAML and then uses the YAML-parser, the conversion seems to
-# slow it down so much that it is only as fast as the JSON::Pure::Parser!
-#
-# If you look at the benchmark data you can see that this is mostly caused by
-# the frequent high outliers - the median of the Rails-parser runs is still
-# overall smaller than the median of the JSON::Pure::Parser runs:
-#
-# Comparing times (call_time_median):
-# 1 ParserBenchmarkExt#parser 900 repeats:
-# 800.592479481 ( real) -> 26.936x
-# 0.001249075
-# 2 ParserBenchmarkYAML#parser 1000 repeats:
-# 271.002390644 ( real) -> 9.118x
-# 0.003690004
-# 3 ParserBenchmarkRails#parser 1000 repeats:
-# 30.227910865 ( real) -> 1.017x
-# 0.033082008
-# 4 ParserBenchmarkPure#parser 1000 repeats:
-# 29.722384421 ( real) -> 1.000x
-# 0.033644676
-# calls/sec ( time) -> speed covers
-# secs/call
-#
-# I have benchmarked the JSON-Generator as well. This generated a few more
-# values, because there are different modes that also influence the achieved
-# speed:
-#
-# Comparing times (call_time_mean):
-# 1 GeneratorBenchmarkExt#generator_fast 1000 repeats:
-# 547.354332608 ( real) -> 15.090x
-# 0.001826970
-# 2 GeneratorBenchmarkExt#generator_safe 1000 repeats:
-# 443.968212317 ( real) -> 12.240x
-# 0.002252414
-# 3 GeneratorBenchmarkExt#generator_pretty 900 repeats:
-# 375.104545883 ( real) -> 10.341x
-# 0.002665923
-# 4 GeneratorBenchmarkPure#generator_fast 1000 repeats:
-# 49.978706968 ( real) -> 1.378x
-# 0.020008521
-# 5 GeneratorBenchmarkRails#generator 1000 repeats:
-# 38.531868759 ( real) -> 1.062x
-# 0.025952543
-# 6 GeneratorBenchmarkPure#generator_safe 1000 repeats:
-# 36.927649925 ( real) -> 1.018x 7 (>=3859)
-# 0.027079979
-# 7 GeneratorBenchmarkPure#generator_pretty 1000 repeats:
-# 36.272134441 ( real) -> 1.000x 6 (>=3859)
-# 0.027569373
-# calls/sec ( time) -> speed covers
-# secs/call
-#
-# In the table above 1-3 are JSON::Ext::Generator methods. 4, 6, and 7 are
-# JSON::Pure::Generator methods and 5 is the Rails JSON generator. It is now a
-# bit faster than the generator_safe and generator_pretty methods of the pure
-# variant but slower than the others.
-#
-# To achieve the fastest JSON text output, you can use the fast_generate
-# method. Beware, that this will disable the checking for circular Ruby data
-# structures, which may cause JSON to go into an infinite loop.
-#
-# Here are the median comparisons for completeness' sake:
-#
-# Comparing times (call_time_median):
-# 1 GeneratorBenchmarkExt#generator_fast 1000 repeats:
-# 708.258020939 ( real) -> 16.547x
-# 0.001411915
-# 2 GeneratorBenchmarkExt#generator_safe 1000 repeats:
-# 569.105020353 ( real) -> 13.296x
-# 0.001757145
-# 3 GeneratorBenchmarkExt#generator_pretty 900 repeats:
-# 482.825371244 ( real) -> 11.280x
-# 0.002071142
-# 4 GeneratorBenchmarkPure#generator_fast 1000 repeats:
-# 62.717626652 ( real) -> 1.465x
-# 0.015944481
-# 5 GeneratorBenchmarkRails#generator 1000 repeats:
-# 43.965681162 ( real) -> 1.027x
-# 0.022745013
-# 6 GeneratorBenchmarkPure#generator_safe 1000 repeats:
-# 43.929073409 ( real) -> 1.026x 7 (>=3859)
-# 0.022763968
-# 7 GeneratorBenchmarkPure#generator_pretty 1000 repeats:
-# 42.802514491 ( real) -> 1.000x 6 (>=3859)
-# 0.023363113
-# calls/sec ( time) -> speed covers
-# secs/call
-#
-# == Examples
-#
-# To create a JSON text from a ruby data structure, you can call JSON.generate
-# like that:
-#
-# json = JSON.generate [1, 2, {"a"=>3.141}, false, true, nil, 4..10]
-# # => "[1,2,{\"a\":3.141},false,true,null,\"4..10\"]"
-#
-# To create a valid JSON text you have to make sure, that the output is
-# embedded in either a JSON array [] or a JSON object {}. The easiest way to do
-# this, is by putting your values in a Ruby Array or Hash instance.
-#
-# To get back a ruby data structure from a JSON text, you have to call
-# JSON.parse on it:
-#
-# JSON.parse json
-# # => [1, 2, {"a"=>3.141}, false, true, nil, "4..10"]
-#
-# Note, that the range from the original data structure is a simple
-# string now. The reason for this is, that JSON doesn't support ranges
-# or arbitrary classes. In this case the json library falls back to call
-# Object#to_json, which is the same as #to_s.to_json.
-#
-# It's possible to add JSON support serialization to arbitrary classes by
-# simply implementing a more specialized version of the #to_json method, that
-# should return a JSON object (a hash converted to JSON with #to_json) like
-# this (don't forget the *a for all the arguments):
-#
-# class Range
-# def to_json(*a)
-# {
-# 'json_class' => self.class.name, # = 'Range'
-# 'data' => [ first, last, exclude_end? ]
-# }.to_json(*a)
-# end
-# end
-#
-# The hash key 'json_class' is the class, that will be asked to deserialise the
-# JSON representation later. In this case it's 'Range', but any namespace of
-# the form 'A::B' or '::A::B' will do. All other keys are arbitrary and can be
-# used to store the necessary data to configure the object to be deserialised.
-#
-# If a the key 'json_class' is found in a JSON object, the JSON parser checks
-# if the given class responds to the json_create class method. If so, it is
-# called with the JSON object converted to a Ruby hash. So a range can
-# be deserialised by implementing Range.json_create like this:
-#
-# class Range
-# def self.json_create(o)
-# new(*o['data'])
-# end
-# end
-#
-# Now it possible to serialise/deserialise ranges as well:
-#
-# json = JSON.generate [1, 2, {"a"=>3.141}, false, true, nil, 4..10]
-# # => "[1,2,{\"a\":3.141},false,true,null,{\"json_class\":\"Range\",\"data\":[4,10,false]}]"
-# JSON.parse json
-# # => [1, 2, {"a"=>3.141}, false, true, nil, 4..10]
-#
-# JSON.generate always creates the shortest possible string representation of a
-# ruby data structure in one line. This good for data storage or network
-# protocols, but not so good for humans to read. Fortunately there's also
-# JSON.pretty_generate (or JSON.pretty_generate) that creates a more
-# readable output:
-#
-# puts JSON.pretty_generate([1, 2, {"a"=>3.141}, false, true, nil, 4..10])
-# [
-# 1,
-# 2,
-# {
-# "a": 3.141
-# },
-# false,
-# true,
-# null,
-# {
-# "json_class": "Range",
-# "data": [
-# 4,
-# 10,
-# false
-# ]
-# }
-# ]
-#
-# There are also the methods Kernel#j for generate, and Kernel#jj for
-# pretty_generate output to the console, that work analogous to Core Ruby's p
-# and the pp library's pp methods.
-#
-# The script tools/server.rb contains a small example if you want to test, how
-# receiving a JSON object from a webrick server in your browser with the
-# javasript prototype library (http://www.prototypejs.org) works.
-#
module JSON
require 'json/version'
- if VARIANT_BINARY
+ begin
require 'json/ext'
- else
- begin
- require 'json/ext'
- rescue LoadError
- require 'json/pure'
- end
+ rescue LoadError
+ require 'json/pure'
end
end