Enhance generic JSON and #generate docs

lib/json.rb

@@ -9,8 +9,11 @@
 # JSON is completely language agnostic, making it the ideal interchange format.
 #
 # Built on two universally available structures:
-#   1. A collection of name/value pairs. Often referred to as an _object_, hash table, record, struct, keyed list, or associative array.
-#   2. An ordered list of values. More commonly called an _array_, vector, sequence or list.
+#
+# 1. A collection of name/value pairs. Often referred to as an _object_, hash table,
+#    record, struct, keyed list, or associative array.
+# 2. An ordered list of values. More commonly called an _array_, vector, sequence or
+#    list.
 #
 # To read more about JSON visit: http://json.org
 #
@@ -22,7 +25,7 @@
 #   require 'json'
 #
 #   my_hash = JSON.parse('{"hello": "goodbye"}')
-#   puts my_hash["hello"] => "goodbye"
+#   puts my_hash["hello"] # => "goodbye"
 #
 # Notice the extra quotes <tt>''</tt> around the hash notation. Ruby expects
 # the argument to be a string and can't convert objects like a hash or array.
@@ -37,13 +40,50 @@
 #   require 'json'
 #
 #   my_hash = {:hello => "goodbye"}
-#   puts JSON.generate(my_hash) => "{\"hello\":\"goodbye\"}"
+#   puts JSON.generate(my_hash) # => "{\"hello\":\"goodbye\"}"
 #
 # Or an alternative way:
 #
 #   require 'json'
-#   puts {:hello => "goodbye"}.to_json => "{\"hello\":\"goodbye\"}"
+#   puts({:hello => "goodbye"}.to_json) # => "{\"hello\":\"goodbye\"}"
+#
+# <tt>JSON.generate</tt> only allows objects or arrays to be converted
+# to JSON syntax. <tt>to_json</tt>, however, accepts many Ruby classes
+# even though it acts only as a method for serialization:
+#
+#   require 'json'
 #
+#   1.to_json # => "1"
+#
+# The {#generate}[rdoc-ref:JSON#generate] method accepts a variety of options
+# to set the formatting of string output and defining what input is accepteable.
+# There are also shortcut methods pretty_generate (with a set of options to
+# generate human-readable multiline JSON) and fast_generate (with a set of
+# options to generate JSON faster at the price of disabling some checks).
+#
+# == Extended rendering and loading of Ruby objects
+#
+# JSON library provides optional _additions_ allowing to serialize and
+# deserialize Ruby classes without loosing their type.
+#
+#   # without additions
+#   require "json"
+#   json = JSON.generate({range: 1..3, regex: /test/})
+#   # => '{"range":"1..3","regex":"(?-mix:test)"}'
+#   JSON.parse(json)
+#   # => {"range"=>"1..3", "regex"=>"(?-mix:test)"}
+#
+#   # with additions
+#   require "json/add/range"
+#   require "json/add/regexp"
+#   json = JSON.generate({range: 1..3, regex: /test/})
+#   # => '{"range":{"json_class":"Range","a":[1,3,false]},"regex":{"json_class":"Regexp","o":0,"s":"test"}}'
+#   JSON.parse(json)
+#   # => {"range"=>{"json_class"=>"Range", "a"=>[1, 3, false]}, "regex"=>{"json_class"=>"Regexp", "o"=>0, "s"=>"test"}}
+#   JSON.load(json)
+#   # => {"range"=>1..3, "regex"=>/test/}
+#
+# See JSON.load for details.
 module JSON
   require 'json/version'
 

lib/json/common.rb

@@ -180,27 +180,30 @@ def parse!(source, opts = {})
   end
 
   # Generate a JSON document from the Ruby data structure _obj_ and return
-  # it. _state_ is * a JSON::State object,
-  # * or a Hash like object (responding to to_hash),
-  # * an object convertible into a hash by a to_h method,
-  # that is used as or to configure a State object.
+  # it. _opts_ is
+  # * a Hash like object (responding to +to_hash+),
+  # * or an object convertible into a hash by a +to_h+ method,
+  # * or a <tt>JSON::State</tt> object.
   #
-  # It defaults to a state object, that creates the shortest possible JSON text
-  # in one line, checks for circular data structures and doesn't allow NaN,
+  # If hash-alike or hash-convertible object is provided, it is internally
+  # converted into a State object.
+  #
+  # The default options are set to create the shortest possible JSON text
+  # in one line, check for circular data structures and do not allow NaN,
   # Infinity, and -Infinity.
   #
-  # A _state_ hash can have the following keys:
-  # * *indent*: a string used to indent levels (default: ''),
-  # * *space*: a string that is put after, a : or , delimiter (default: ''),
-  # * *space_before*: a string that is put before a : pair delimiter (default: ''),
-  # * *object_nl*: a string that is put at the end of a JSON object (default: ''),
-  # * *array_nl*: a string that is put at the end of a JSON array (default: ''),
+  # An _opts_ hash can have the following keys:
+  # * *indent*: a string used to indent levels (default: <tt>''</tt>),
+  # * *space*: a string that is put after a <tt>:</tt> pair delimiter (default: <tt>''</tt>),
+  # * *space_before*: a string that is put before a <tt>:</tt> pair delimiter (default: <tt>''</tt>),
+  # * *object_nl*: a string that is put at the end of a JSON object (default: <tt>''</tt>),
+  # * *array_nl*: a string that is put at the end of a JSON array (default: <tt>''</tt>),
   # * *allow_nan*: true if NaN, Infinity, and -Infinity should be
   #   generated, otherwise an exception is thrown if these values are
   #   encountered. This options defaults to false.
   # * *max_nesting*: The maximum depth of nesting allowed in the data
   #   structures from which JSON is to be generated. Disable depth checking
-  #   with :max_nesting => false, it defaults to 100.
+  #   with <tt>max_nesting: false</tt>, it defaults to 100.
   #
   # See also the fast_generate for the fastest creation method with the least
   # amount of sanity checks, and the pretty_generate method for some