# File lib/neovim/logging.rb, line 15
    def self.logger(env=ENV)
      return @logger if instance_variable_defined?(:@logger)

      if env_file = env["NVIM_RUBY_LOG_FILE"]
        @logger = Logger.new(env_file)
      else
        @logger = Logger.new(STDERR)
      end

      if env_level = env["NVIM_RUBY_LOG_LEVEL"]
        begin
          @logger.level = Integer(env_level)
        rescue ArgumentError
          @logger.level = Logger.const_get(env_level.upcase)
        end
      else
        @logger.level = Logger::WARN
      end

      @logger
    end