diff -r ffa851df0825 -r 2fb8b9db1c86 symbian-qemu-0.9.1-12/python-2.6.1/Doc/includes/tzinfo-examples.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/symbian-qemu-0.9.1-12/python-2.6.1/Doc/includes/tzinfo-examples.py Fri Jul 31 15:01:17 2009 +0100 @@ -0,0 +1,169 @@ +from datetime import tzinfo, timedelta, datetime + +ZERO = timedelta(0) +HOUR = timedelta(hours=1) + +# A UTC class. + +class UTC(tzinfo): + """UTC""" + + def utcoffset(self, dt): + return ZERO + + def tzname(self, dt): + return "UTC" + + def dst(self, dt): + return ZERO + +utc = UTC() + +# A class building tzinfo objects for fixed-offset time zones. +# Note that FixedOffset(0, "UTC") is a different way to build a +# UTC tzinfo object. + +class FixedOffset(tzinfo): + """Fixed offset in minutes east from UTC.""" + + def __init__(self, offset, name): + self.__offset = timedelta(minutes = offset) + self.__name = name + + def utcoffset(self, dt): + return self.__offset + + def tzname(self, dt): + return self.__name + + def dst(self, dt): + return ZERO + +# A class capturing the platform's idea of local time. + +import time as _time + +STDOFFSET = timedelta(seconds = -_time.timezone) +if _time.daylight: + DSTOFFSET = timedelta(seconds = -_time.altzone) +else: + DSTOFFSET = STDOFFSET + +DSTDIFF = DSTOFFSET - STDOFFSET + +class LocalTimezone(tzinfo): + + def utcoffset(self, dt): + if self._isdst(dt): + return DSTOFFSET + else: + return STDOFFSET + + def dst(self, dt): + if self._isdst(dt): + return DSTDIFF + else: + return ZERO + + def tzname(self, dt): + return _time.tzname[self._isdst(dt)] + + def _isdst(self, dt): + tt = (dt.year, dt.month, dt.day, + dt.hour, dt.minute, dt.second, + dt.weekday(), 0, -1) + stamp = _time.mktime(tt) + tt = _time.localtime(stamp) + return tt.tm_isdst > 0 + +Local = LocalTimezone() + + +# A complete implementation of current DST rules for major US time zones. + +def first_sunday_on_or_after(dt): + days_to_go = 6 - dt.weekday() + if days_to_go: + dt += timedelta(days_to_go) + return dt + + +# US DST Rules +# +# This is a simplified (i.e., wrong for a few cases) set of rules for US +# DST start and end times. For a complete and up-to-date set of DST rules +# and timezone definitions, visit the Olson Database (or try pytz): +# http://www.twinsun.com/tz/tz-link.htm +# http://sourceforge.net/projects/pytz/ (might not be up-to-date) +# +# In the US, since 2007, DST starts at 2am (standard time) on the second +# Sunday in March, which is the first Sunday on or after Mar 8. +DSTSTART_2007 = datetime(1, 3, 8, 2) +# and ends at 2am (DST time; 1am standard time) on the first Sunday of Nov. +DSTEND_2007 = datetime(1, 11, 1, 1) +# From 1987 to 2006, DST used to start at 2am (standard time) on the first +# Sunday in April and to end at 2am (DST time; 1am standard time) on the last +# Sunday of October, which is the first Sunday on or after Oct 25. +DSTSTART_1987_2006 = datetime(1, 4, 1, 2) +DSTEND_1987_2006 = datetime(1, 10, 25, 1) +# From 1967 to 1986, DST used to start at 2am (standard time) on the last +# Sunday in April (the one on or after April 24) and to end at 2am (DST time; +# 1am standard time) on the last Sunday of October, which is the first Sunday +# on or after Oct 25. +DSTSTART_1967_1986 = datetime(1, 4, 24, 2) +DSTEND_1967_1986 = DSTEND_1987_2006 + +class USTimeZone(tzinfo): + + def __init__(self, hours, reprname, stdname, dstname): + self.stdoffset = timedelta(hours=hours) + self.reprname = reprname + self.stdname = stdname + self.dstname = dstname + + def __repr__(self): + return self.reprname + + def tzname(self, dt): + if self.dst(dt): + return self.dstname + else: + return self.stdname + + def utcoffset(self, dt): + return self.stdoffset + self.dst(dt) + + def dst(self, dt): + if dt is None or dt.tzinfo is None: + # An exception may be sensible here, in one or both cases. + # It depends on how you want to treat them. The default + # fromutc() implementation (called by the default astimezone() + # implementation) passes a datetime with dt.tzinfo is self. + return ZERO + assert dt.tzinfo is self + + # Find start and end times for US DST. For years before 1967, return + # ZERO for no DST. + if 2006 < dt.year: + dststart, dstend = DSTSTART_2007, DSTEND_2007 + elif 1986 < dt.year < 2007: + dststart, dstend = DSTSTART_1987_2006, DSTEND_1987_2006 + elif 1966 < dt.year < 1987: + dststart, dstend = DSTSTART_1967_1986, DSTEND_1967_1986 + else: + return ZERO + + start = first_sunday_on_or_after(dststart.replace(year=dt.year)) + end = first_sunday_on_or_after(dstend.replace(year=dt.year)) + + # Can't compare naive to aware objects, so strip the timezone from + # dt first. + if start <= dt.replace(tzinfo=None) < end: + return HOUR + else: + return ZERO + +Eastern = USTimeZone(-5, "Eastern", "EST", "EDT") +Central = USTimeZone(-6, "Central", "CST", "CDT") +Mountain = USTimeZone(-7, "Mountain", "MST", "MDT") +Pacific = USTimeZone(-8, "Pacific", "PST", "PDT")