Turn Util::Json also into singleton.

require 'jsduck/util/singleton'

require 'jsduck/util/io'

require 'jsduck/logger'

require 'json'

    # The main benefit of it is that we have a central place for

    # controlling how the JSON is created (pretty-formatted or not).

    class Json

      @@pretty = false

      include Util::Singleton

      def initialize

        @pretty = false

      end

      # Set to true to turn on pretty-formatting of JSON

      def self.pretty=(pretty)

        @@pretty = pretty

      def pretty=(pretty)

        @pretty = pretty

      end

      # Turns object into JSON, places it inside JavaScript that calls the

      # given callback name, and writes the result to file.

      def self.write_jsonp(filename, callback_name, data)

        jsonp = "Ext.data.JsonP." + callback_name + "(" + self.generate(data) + ");"

      def write_jsonp(filename, callback_name, data)

        jsonp = "Ext.data.JsonP." + callback_name + "(" + generate(data) + ");"

        File.open(filename, 'w') {|f| f.write(jsonp) }

      end

      # Turns object into JSON and writes inside a file

      def self.write_json(filename, data)

        File.open(filename, 'w') {|f| f.write(self.generate(data)) }

      def write_json(filename, data)

        File.open(filename, 'w') {|f| f.write(generate(data)) }

      end

      # Generates JSON from object

      def self.generate(data)

        @@pretty ? JSON.pretty_generate(data) : JSON.generate(data)

      def generate(data)

        @pretty ? JSON.pretty_generate(data) : JSON.generate(data)

      end

      # Reads and parses JSON from file

      def self.read(filename)

      def read(filename)

        begin

          self.parse(Util::IO.read(filename))

          parse(Util::IO.read(filename))

        rescue

          Logger.fatal("#{filename} is not a valid JSON file")

          exit(1)

      end

      # Parses JSON string

      def self.parse(string)

      def parse(string)

        JSON.parse(string)

      end