Move rational and complex additions in own files

Also do not require Ruby's complex.rb and rational.rb if the top level
constants are already defined. This means Ruby 1.9 implementations are
extendend, but Ruby 1.8 implementations will require rational/complex
before they are extended. Having rational and complex additions in their
own files is an especially good thing, if one wants to avoid loading
complex and rational under Ruby 1.8.

1 files changed, 22 insertions, 0 deletions

diff --git a/lib/json/add/rational.rb b/lib/json/add/rational.rb
new file mode 100644
index 0000000..867cd92
--- /dev/null
+++ b/lib/json/add/rational.rb
@@ -0,0 +1,22 @@
+unless defined?(::JSON::JSON_LOADED) and ::JSON::JSON_LOADED
+  require 'json'
+end
+defined?(::Rational) or require 'rational'
+
+class Rational
+  def self.json_create(object)
+    Rational(object['n'], object['d'])
+  end
+
+  def as_json(*)
+    {
+      JSON.create_id => self.class.name,
+      'n'            => numerator,
+      'd'            => denominator,
+    }
+  end
+
+  def to_json(*)
+    as_json.to_json
+  end
+end