# This file is part of NIT ( http://www.nitlanguage.org ). # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.orglicensesLICENSE2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # This module provide a simple wall clock. # It is an example of getters and setters. # A beefed-up module is available in clock_more module clock # A simple wall clock with 60 minutes and 12 hours. class Clock # total number of minutes from 0 to 719 var total_minutes: Int # Note: only the read acces is public, the write access is private. # number of minutes in the current hour (from 0 to 59) fun minutes: Int do return self.total_minutes % 60 # set the number of minutes in the current hour. # if m < 0 or m >= 60, the hour will be changed accordinlgy fun minutes(m: Int) do self.total_minutes = self.hours * 60 + m # number of hours (from 0 to 11) fun hours: Int do return self.total_minutes / 60 # set the number of hours # the minutes will not be updated fun hours(h: Int) do self.total_minutes = h * 60 + minutes # the position of the hour arrow in the [0..60[ interval fun hour_pos: Int do return total_minutes / 12 # replace the arrow of hours (from 0 to 59). # the hours and the minutes will be updated. fun hour_pos(h: Int) do self.total_minutes = h * 12 redef fun to_s do return "{hours}:{minutes}" fun reset(hours, minutes: Int) do self.total_minutes = hours60 + minutes init(hours, minutes: Int) do self.reset(hours, minutes) redef fun ==(o) do # Note: o is a nullable Object, a type test is required # Thanks to adaptive typing, there is no downcast # i.e. the code is safe return o isa Clock and self.total_minutes == o.total_minutes end end var c = new Clock(10,50) print "It's {c} o'clock." c.minutes += 22 print "Now it's {c} o'clock." print "The short arrow in on the {c.hour_pos/5} and the long arrow in on the {c.minutes/5}." c.hours -= 2 print "Now it's {c} o'clock." var c2 = new Clock(9, 11) print "It's {c2} on the second clock." print "The two clocks are synchronized: {c == c2}." c2.minutes += 1 print "It's now {c2} on the second clock." print "The two clocks are synchronized: {c == c2}."