Contents

module RiCal
  class PropertyValue
    #- ©2009 Rick DeNatale
    #- All rights reserved. Refer to the file README.txt for the license
    #
    # Methods for DateTime which support adding or subtracting another DateTime or Duration
    module AdditiveMethods
      #  if end_time is nil => nil
      #  otherwise convert end_time to a DateTime and compute the difference
      def duration_until(end_time) # :nodoc:
        end_time  && RiCal::PropertyValue::Duration.from_datetimes(timezone_finder, to_datetime, end_time.to_datetime)
      end

      # Double-dispatch method for subtraction.
      def subtract_from_date_time_value(dtvalue) #:nodoc:
        RiCal::PropertyValue::Duration.from_datetimes(timezone_finder, to_datetime,dtvalue.to_datetime)
      end

      # Double-dispatch method for addition.
      def add_to_date_time_value(date_time_value) #:nodoc:
        raise ArgumentError.new("Cannot add #{date_time_value} to #{self}")
      end

      # Return the difference between the receiver and other
      #
      # The parameter other should be either a RiCal::PropertyValue::Duration or a RiCal::PropertyValue::DateTime
      #
      # If other is a Duration, the result will be a DateTime, if it is a DateTime the result will be a Duration
      def -(other)
        other.subtract_from_date_time_value(self)
      end

      # Return the sum of the receiver and duration
      #
      # The parameter other duration should be  a RiCal::PropertyValue::Duration
      #
      # The result will be an RiCal::PropertyValue::DateTime
      def +(duration)
        duration.add_to_date_time_value(self)
      end
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
rubyredrick-ri_cal-0.0.2	lib/ri_cal/property_value/date_time/additive_methods.rb