1 #
2 # Copyright (c) 2001 Bizar Software Pty Ltd (http://www.bizarsoftware.com.au/)
3 # This module is free software, and you may redistribute it and/or modify
4 # under the same terms as Python, so long as this copyright message and
5 # disclaimer are retained in their original form.
6 #
7 # IN NO EVENT SHALL BIZAR SOFTWARE PTY LTD BE LIABLE TO ANY PARTY FOR
8 # DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
9 # OUT OF THE USE OF THIS CODE, EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE
10 # POSSIBILITY OF SUCH DAMAGE.
11 #
12 # BIZAR SOFTWARE PTY LTD SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
13 # BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
14 # FOR A PARTICULAR PURPOSE. THE CODE PROVIDED HEREUNDER IS ON AN "AS IS"
15 # BASIS, AND THERE IS NO OBLIGATION WHATSOEVER TO PROVIDE MAINTENANCE,
16 # SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
17 #
18 # $Id: date.py,v 1.54 2003-04-23 11:48:05 richard Exp $
20 __doc__ = """
21 Date, time and time interval handling.
22 """
24 import time, re, calendar, types
25 from i18n import _
27 def _add_granularity(src, order, value = 1):
28 '''Increment first non-None value in src dictionary ordered by 'order'
29 parameter
30 '''
31 for gran in order:
32 if src[gran]:
33 src[gran] = int(src[gran]) + value
34 break
36 class Date:
37 '''
38 As strings, date-and-time stamps are specified with the date in
39 international standard format (yyyy-mm-dd) joined to the time
40 (hh:mm:ss) by a period ("."). Dates in this form can be easily compared
41 and are fairly readable when printed. An example of a valid stamp is
42 "2000-06-24.13:03:59". We'll call this the "full date format". When
43 Timestamp objects are printed as strings, they appear in the full date
44 format with the time always given in GMT. The full date format is
45 always exactly 19 characters long.
47 For user input, some partial forms are also permitted: the whole time
48 or just the seconds may be omitted; and the whole date may be omitted
49 or just the year may be omitted. If the time is given, the time is
50 interpreted in the user's local time zone. The Date constructor takes
51 care of these conversions. In the following examples, suppose that yyyy
52 is the current year, mm is the current month, and dd is the current day
53 of the month; and suppose that the user is on Eastern Standard Time.
55 "2000-04-17" means <Date 2000-04-17.00:00:00>
56 "01-25" means <Date yyyy-01-25.00:00:00>
57 "2000-04-17.03:45" means <Date 2000-04-17.08:45:00>
58 "08-13.22:13" means <Date yyyy-08-14.03:13:00>
59 "11-07.09:32:43" means <Date yyyy-11-07.14:32:43>
60 "14:25" means <Date yyyy-mm-dd.19:25:00>
61 "8:47:11" means <Date yyyy-mm-dd.13:47:11>
62 "2003" means <Date 2003-01-01.00:00:00>
63 "2003-06" means <Date 2003-06-01.00:00:00>
64 "." means "right now"
66 The Date class should understand simple date expressions of the form
67 stamp + interval and stamp - interval. When adding or subtracting
68 intervals involving months or years, the components are handled
69 separately. For example, when evaluating "2000-06-25 + 1m 10d", we
70 first add one month to get 2000-07-25, then add 10 days to get
71 2000-08-04 (rather than trying to decide whether 1m 10d means 38 or 40
72 or 41 days).
74 Example usage:
75 >>> Date(".")
76 <Date 2000-06-26.00:34:02>
77 >>> _.local(-5)
78 "2000-06-25.19:34:02"
79 >>> Date(". + 2d")
80 <Date 2000-06-28.00:34:02>
81 >>> Date("1997-04-17", -5)
82 <Date 1997-04-17.00:00:00>
83 >>> Date("01-25", -5)
84 <Date 2000-01-25.00:00:00>
85 >>> Date("08-13.22:13", -5)
86 <Date 2000-08-14.03:13:00>
87 >>> Date("14:25", -5)
88 <Date 2000-06-25.19:25:00>
90 The date format 'yyyymmddHHMMSS' (year, month, day, hour,
91 minute, second) is the serialisation format returned by the serialise()
92 method, and is accepted as an argument on instatiation.
93 '''
95 def __init__(self, spec='.', offset=0, add_granularity=0):
96 """Construct a date given a specification and a time zone offset.
98 'spec' is a full date or a partial form, with an optional
99 added or subtracted interval. Or a date 9-tuple.
100 'offset' is the local time zone offset from GMT in hours.
101 """
102 if type(spec) == type(''):
103 self.set(spec, offset=offset, add_granularity=add_granularity)
104 else:
105 y,m,d,H,M,S,x,x,x = spec
106 ts = calendar.timegm((y,m,d,H+offset,M,S,0,0,0))
107 self.year, self.month, self.day, self.hour, self.minute, \
108 self.second, x, x, x = time.gmtime(ts)
110 usagespec='[yyyy]-[mm]-[dd].[H]H:MM[:SS][offset]'
111 def set(self, spec, offset=0, date_re=re.compile(r'''
112 ((?P<y>\d\d\d\d)([/-](?P<m>\d\d?)([/-](?P<d>\d\d?))?)? # yyyy[-mm[-dd]]
113 |(?P<a>\d\d?)[/-](?P<b>\d\d?))? # or mm-dd
114 (?P<n>\.)? # .
115 (((?P<H>\d?\d):(?P<M>\d\d))?(:(?P<S>\d\d))?)? # hh:mm:ss
116 (?P<o>.+)? # offset
117 ''', re.VERBOSE), serialised_re=re.compile(r'''
118 (\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)
119 ''', re.VERBOSE), add_granularity=0):
120 ''' set the date to the value in spec
121 '''
123 m = serialised_re.match(spec)
124 if m is not None:
125 # we're serialised - easy!
126 self.year, self.month, self.day, self.hour, self.minute, \
127 self.second = map(int, m.groups()[:6])
128 return
130 # not serialised data, try usual format
131 m = date_re.match(spec)
132 if m is None:
133 raise ValueError, _('Not a date spec: %s' % self.usagespec)
135 info = m.groupdict()
137 if add_granularity:
138 _add_granularity(info, 'SMHdmyab')
140 # get the current date as our default
141 y,m,d,H,M,S,x,x,x = time.gmtime(time.time())
143 if info['y'] is not None or info['a'] is not None:
144 if info['y'] is not None:
145 y = int(info['y'])
146 m,d = (1,1)
147 if info['m'] is not None:
148 m = int(info['m'])
149 if info['d'] is not None:
150 d = int(info['d'])
151 if info['a'] is not None:
152 m = int(info['a'])
153 d = int(info['b'])
154 H = -offset
155 M = S = 0
157 # override hour, minute, second parts
158 if info['H'] is not None and info['M'] is not None:
159 H = int(info['H']) - offset
160 M = int(info['M'])
161 S = 0
162 if info['S'] is not None: S = int(info['S'])
164 if add_granularity:
165 S = S - 1
167 # now handle the adjustment of hour
168 ts = calendar.timegm((y,m,d,H,M,S,0,0,0))
169 self.year, self.month, self.day, self.hour, self.minute, \
170 self.second, x, x, x = time.gmtime(ts)
172 if info.get('o', None):
173 try:
174 self.applyInterval(Interval(info['o'], allowdate=0))
175 except ValueError:
176 raise ValueError, _('Not a date spec: %s' % self.usagespec)
178 def addInterval(self, interval):
179 ''' Add the interval to this date, returning the date tuple
180 '''
181 # do the basic calc
182 sign = interval.sign
183 year = self.year + sign * interval.year
184 month = self.month + sign * interval.month
185 day = self.day + sign * interval.day
186 hour = self.hour + sign * interval.hour
187 minute = self.minute + sign * interval.minute
188 second = self.second + sign * interval.second
190 # now cope with under- and over-flow
191 # first do the time
192 while (second < 0 or second > 59 or minute < 0 or minute > 59 or
193 hour < 0 or hour > 59):
194 if second < 0: minute -= 1; second += 60
195 elif second > 59: minute += 1; second -= 60
196 if minute < 0: hour -= 1; minute += 60
197 elif minute > 59: hour += 1; minute -= 60
198 if hour < 0: day -= 1; hour += 24
199 elif hour > 59: day += 1; hour -= 24
201 # fix up the month so we're within range
202 while month < 1 or month > 12:
203 if month < 1: year -= 1; month += 12
204 if month > 12: year += 1; month -= 12
206 # now do the days, now that we know what month we're in
207 mdays = calendar.mdays
208 if month == 2 and calendar.isleap(year): month_days = 29
209 else: month_days = mdays[month]
210 while month < 1 or month > 12 or day < 0 or day > month_days:
211 # now to day under/over
212 if day < 0: month -= 1; day += month_days
213 elif day > month_days: month += 1; day -= month_days
215 # possibly fix up the month so we're within range
216 while month < 1 or month > 12:
217 if month < 1: year -= 1; month += 12
218 if month > 12: year += 1; month -= 12
220 # re-figure the number of days for this month
221 if month == 2 and calendar.isleap(year): month_days = 29
222 else: month_days = mdays[month]
223 return (year, month, day, hour, minute, second, 0, 0, 0)
225 def applyInterval(self, interval):
226 ''' Apply the interval to this date
227 '''
228 self.year, self.month, self.day, self.hour, self.minute, \
229 self.second, x, x, x = self.addInterval(interval)
231 def __add__(self, interval):
232 """Add an interval to this date to produce another date.
233 """
234 return Date(self.addInterval(interval))
236 # deviates from spec to allow subtraction of dates as well
237 def __sub__(self, other):
238 """ Subtract:
239 1. an interval from this date to produce another date.
240 2. a date from this date to produce an interval.
241 """
242 if isinstance(other, Interval):
243 other = Interval(other.get_tuple())
244 other.sign *= -1
245 return self.__add__(other)
247 assert isinstance(other, Date), 'May only subtract Dates or Intervals'
249 # TODO this code will fall over laughing if the dates cross
250 # leap years, phases of the moon, ....
251 a = calendar.timegm((self.year, self.month, self.day, self.hour,
252 self.minute, self.second, 0, 0, 0))
253 b = calendar.timegm((other.year, other.month, other.day,
254 other.hour, other.minute, other.second, 0, 0, 0))
255 diff = a - b
256 if diff < 0:
257 sign = 1
258 diff = -diff
259 else:
260 sign = -1
261 S = diff%60
262 M = (diff/60)%60
263 H = (diff/(60*60))%60
264 if H>1: S = 0
265 d = (diff/(24*60*60))%30
266 if d>1: H = S = M = 0
267 m = (diff/(30*24*60*60))%12
268 if m>1: H = S = M = 0
269 y = (diff/(365*24*60*60))
270 if y>1: d = H = S = M = 0
271 return Interval((y, m, d, H, M, S), sign=sign)
273 def __cmp__(self, other):
274 """Compare this date to another date."""
275 if other is None:
276 return 1
277 for attr in ('year', 'month', 'day', 'hour', 'minute', 'second'):
278 if not hasattr(other, attr):
279 return 1
280 r = cmp(getattr(self, attr), getattr(other, attr))
281 if r: return r
282 return 0
284 def __str__(self):
285 """Return this date as a string in the yyyy-mm-dd.hh:mm:ss format."""
286 return '%4d-%02d-%02d.%02d:%02d:%02d'%(self.year, self.month, self.day,
287 self.hour, self.minute, self.second)
289 def pretty(self, format='%d %B %Y'):
290 ''' print up the date date using a pretty format...
292 Note that if the day is zero, and the day appears first in the
293 format, then the day number will be removed from output.
294 '''
295 str = time.strftime(format, (self.year, self.month, self.day,
296 self.hour, self.minute, self.second, 0, 0, 0))
297 # handle zero day by removing it
298 if format.startswith('%d') and str[0] == '0':
299 return ' ' + str[1:]
300 return str
302 def __repr__(self):
303 return '<Date %s>'%self.__str__()
305 def local(self, offset):
306 """ Return this date as yyyy-mm-dd.hh:mm:ss in a local time zone.
307 """
308 return Date((self.year, self.month, self.day, self.hour + offset,
309 self.minute, self.second, 0, 0, 0))
311 def get_tuple(self):
312 return (self.year, self.month, self.day, self.hour, self.minute,
313 self.second, 0, 0, 0)
315 def serialise(self):
316 return '%4d%02d%02d%02d%02d%02d'%(self.year, self.month,
317 self.day, self.hour, self.minute, self.second)
319 class Interval:
320 '''
321 Date intervals are specified using the suffixes "y", "m", and "d". The
322 suffix "w" (for "week") means 7 days. Time intervals are specified in
323 hh:mm:ss format (the seconds may be omitted, but the hours and minutes
324 may not).
326 "3y" means three years
327 "2y 1m" means two years and one month
328 "1m 25d" means one month and 25 days
329 "2w 3d" means two weeks and three days
330 "1d 2:50" means one day, two hours, and 50 minutes
331 "14:00" means 14 hours
332 "0:04:33" means four minutes and 33 seconds
334 Example usage:
335 >>> Interval(" 3w 1 d 2:00")
336 <Interval + 22d 2:00>
337 >>> Date(". + 2d") + Interval("- 3w")
338 <Date 2000-06-07.00:34:02>
339 >>> Interval('1:59:59') + Interval('00:00:01')
340 <Interval + 2:00>
341 >>> Interval('2:00') + Interval('- 00:00:01')
342 <Interval + 1:59:59>
343 >>> Interval('1y')/2
344 <Interval + 6m>
345 >>> Interval('1:00')/2
346 <Interval + 0:30>
347 >>> Interval('2003-03-18')
348 <Interval + [number of days between now and 2003-03-18]>
349 >>> Interval('-4d 2003-03-18')
350 <Interval + [number of days between now and 2003-03-14]>
352 Interval arithmetic is handled in a couple of special ways, trying
353 to cater for the most common cases. Fundamentally, Intervals which
354 have both date and time parts will result in strange results in
355 arithmetic - because of the impossibility of handling day->month->year
356 over- and under-flows. Intervals may also be divided by some number.
358 Intervals are added to Dates in order of:
359 seconds, minutes, hours, years, months, days
361 Calculations involving months (eg '+2m') have no effect on days - only
362 days (or over/underflow from hours/mins/secs) will do that, and
363 days-per-month and leap years are accounted for. Leap seconds are not.
365 The interval format 'syyyymmddHHMMSS' (sign, year, month, day, hour,
366 minute, second) is the serialisation format returned by the serialise()
367 method, and is accepted as an argument on instatiation.
369 TODO: more examples, showing the order of addition operation
370 '''
371 def __init__(self, spec, sign=1, allowdate=1, add_granularity=0):
372 """Construct an interval given a specification."""
373 if type(spec) == type(''):
374 self.set(spec, allowdate=allowdate, add_granularity=add_granularity)
375 else:
376 if len(spec) == 7:
377 self.sign, self.year, self.month, self.day, self.hour, \
378 self.minute, self.second = spec
379 else:
380 # old, buggy spec form
381 self.sign = sign
382 self.year, self.month, self.day, self.hour, self.minute, \
383 self.second = spec
385 def set(self, spec, allowdate=1, interval_re=re.compile('''
386 \s*(?P<s>[-+])? # + or -
387 \s*((?P<y>\d+\s*)y)? # year
388 \s*((?P<m>\d+\s*)m)? # month
389 \s*((?P<w>\d+\s*)w)? # week
390 \s*((?P<d>\d+\s*)d)? # day
391 \s*(((?P<H>\d+):(?P<M>\d+))?(:(?P<S>\d+))?)? # time
392 \s*(?P<D>
393 (\d\d\d\d[/-])?(\d\d?)?[/-](\d\d?)? # [yyyy-]mm-dd
394 \.? # .
395 (\d?\d:\d\d)?(:\d\d)? # hh:mm:ss
396 )?''', re.VERBOSE), serialised_re=re.compile('''
397 (?P<s>[+-])?1?(?P<y>([ ]{3}\d|\d{4}))(?P<m>\d{2})(?P<d>\d{2})
398 (?P<H>\d{2})(?P<M>\d{2})(?P<S>\d{2})''', re.VERBOSE),
399 add_granularity=0):
400 ''' set the date to the value in spec
401 '''
402 self.year = self.month = self.week = self.day = self.hour = \
403 self.minute = self.second = 0
404 self.sign = 1
405 m = serialised_re.match(spec)
406 if not m:
407 m = interval_re.match(spec)
408 if not m:
409 raise ValueError, _('Not an interval spec: [+-] [#y] [#m] [#w] '
410 '[#d] [[[H]H:MM]:SS] [date spec]')
411 else:
412 allowdate = 0
414 # pull out all the info specified
415 info = m.groupdict()
416 if add_granularity:
417 _add_granularity(info, 'SMHdwmy', (info['s']=='-' and -1 or 1))
419 valid = 0
420 for group, attr in {'y':'year', 'm':'month', 'w':'week', 'd':'day',
421 'H':'hour', 'M':'minute', 'S':'second'}.items():
422 if info.get(group, None) is not None:
423 valid = 1
424 setattr(self, attr, int(info[group]))
426 # make sure it's valid
427 if not valid and not info['D']:
428 raise ValueError, _('Not an interval spec: [+-] [#y] [#m] [#w] '
429 '[#d] [[[H]H:MM]:SS]')
431 if self.week:
432 self.day = self.day + self.week*7
434 if info['s'] is not None:
435 self.sign = {'+':1, '-':-1}[info['s']]
437 # use a date spec if one is given
438 if allowdate and info['D'] is not None:
439 now = Date('.')
440 date = Date(info['D'])
441 # if no time part was specified, nuke it in the "now" date
442 if not date.hour or date.minute or date.second:
443 now.hour = now.minute = now.second = 0
444 if date != now:
445 y = now - (date + self)
446 self.__init__(y.get_tuple())
448 def __cmp__(self, other):
449 """Compare this interval to another interval."""
450 if other is None:
451 # we are always larger than None
452 return 1
453 for attr in 'sign year month day hour minute second'.split():
454 r = cmp(getattr(self, attr), getattr(other, attr))
455 if r:
456 return r
457 return 0
459 def __str__(self):
460 """Return this interval as a string."""
461 l = []
462 if self.year: l.append('%sy'%self.year)
463 if self.month: l.append('%sm'%self.month)
464 if self.day: l.append('%sd'%self.day)
465 if self.second:
466 l.append('%d:%02d:%02d'%(self.hour, self.minute, self.second))
467 elif self.hour or self.minute:
468 l.append('%d:%02d'%(self.hour, self.minute))
469 if l:
470 l.insert(0, {1:'+', -1:'-'}[self.sign])
471 return ' '.join(l)
473 def __add__(self, other):
474 if isinstance(other, Date):
475 # the other is a Date - produce a Date
476 return Date(other.addInterval(self))
477 elif isinstance(other, Interval):
478 # add the other Interval to this one
479 a = self.get_tuple()
480 as = a[0]
481 b = other.get_tuple()
482 bs = b[0]
483 i = [as*x + bs*y for x,y in zip(a[1:],b[1:])]
484 i.insert(0, 1)
485 i = fixTimeOverflow(i)
486 return Interval(i)
487 # nope, no idea what to do with this other...
488 raise TypeError, "Can't add %r"%other
490 def __sub__(self, other):
491 if isinstance(other, Date):
492 # the other is a Date - produce a Date
493 interval = Interval(self.get_tuple())
494 interval.sign *= -1
495 return Date(other.addInterval(interval))
496 elif isinstance(other, Interval):
497 # add the other Interval to this one
498 a = self.get_tuple()
499 as = a[0]
500 b = other.get_tuple()
501 bs = b[0]
502 i = [as*x - bs*y for x,y in zip(a[1:],b[1:])]
503 i.insert(0, 1)
504 i = fixTimeOverflow(i)
505 return Interval(i)
506 # nope, no idea what to do with this other...
507 raise TypeError, "Can't add %r"%other
509 def __div__(self, other):
510 ''' Divide this interval by an int value.
512 Can't divide years and months sensibly in the _same_
513 calculation as days/time, so raise an error in that situation.
514 '''
515 try:
516 other = float(other)
517 except TypeError:
518 raise ValueError, "Can only divide Intervals by numbers"
520 y, m, d, H, M, S = (self.year, self.month, self.day,
521 self.hour, self.minute, self.second)
522 if y or m:
523 if d or H or M or S:
524 raise ValueError, "Can't divide Interval with date and time"
525 months = self.year*12 + self.month
526 months *= self.sign
528 months = int(months/other)
530 sign = months<0 and -1 or 1
531 m = months%12
532 y = months / 12
533 return Interval((sign, y, m, 0, 0, 0, 0))
535 else:
536 # handle a day/time division
537 seconds = S + M*60 + H*60*60 + d*60*60*24
538 seconds *= self.sign
540 seconds = int(seconds/other)
542 sign = seconds<0 and -1 or 1
543 seconds *= sign
544 S = seconds%60
545 seconds /= 60
546 M = seconds%60
547 seconds /= 60
548 H = seconds%24
549 d = seconds / 24
550 return Interval((sign, 0, 0, d, H, M, S))
552 def __repr__(self):
553 return '<Interval %s>'%self.__str__()
555 def pretty(self):
556 ''' print up the date date using one of these nice formats..
557 '''
558 if self.year:
559 if self.year == 1:
560 return _('1 year')
561 else:
562 return _('%(number)s years')%{'number': self.year}
563 elif self.month or self.day > 13:
564 days = (self.month * 30) + self.day
565 if days > 28:
566 if int(days/30) > 1:
567 s = _('%(number)s months')%{'number': int(days/30)}
568 else:
569 s = _('1 month')
570 else:
571 s = _('%(number)s weeks')%{'number': int(days/7)}
572 elif self.day > 7:
573 s = _('1 week')
574 elif self.day > 1:
575 s = _('%(number)s days')%{'number': self.day}
576 elif self.day == 1 or self.hour > 12:
577 if self.sign > 0:
578 return _('tomorrow')
579 else:
580 return _('yesterday')
581 elif self.hour > 1:
582 s = _('%(number)s hours')%{'number': self.hour}
583 elif self.hour == 1:
584 if self.minute < 15:
585 s = _('an hour')
586 elif self.minute/15 == 2:
587 s = _('1 1/2 hours')
588 else:
589 s = _('1 %(number)s/4 hours')%{'number': self.minute/15}
590 elif self.minute < 1:
591 if self.sign > 0:
592 return _('in a moment')
593 else:
594 return _('just now')
595 elif self.minute == 1:
596 s = _('1 minute')
597 elif self.minute < 15:
598 s = _('%(number)s minutes')%{'number': self.minute}
599 elif int(self.minute/15) == 2:
600 s = _('1/2 an hour')
601 else:
602 s = _('%(number)s/4 hour')%{'number': int(self.minute/15)}
603 if self.sign < 0:
604 s = s + _(' ago')
605 else:
606 s = _('in ') + s
607 return s
609 def get_tuple(self):
610 return (self.sign, self.year, self.month, self.day, self.hour,
611 self.minute, self.second)
613 def serialise(self):
614 sign = self.sign > 0 and '+' or '-'
615 return '%s%04d%02d%02d%02d%02d%02d'%(sign, self.year, self.month,
616 self.day, self.hour, self.minute, self.second)
618 def fixTimeOverflow(time):
619 ''' Handle the overflow in the time portion (H, M, S) of "time":
620 (sign, y,m,d,H,M,S)
622 Overflow and underflow will at most affect the _days_ portion of
623 the date. We do not overflow days to months as we don't know _how_
624 to, generally.
625 '''
626 # XXX we could conceivably use this function for handling regular dates
627 # XXX too - we just need to interrogate the month/year for the day
628 # XXX overflow...
630 sign, y, m, d, H, M, S = time
631 seconds = sign * (S + M*60 + H*60*60 + d*60*60*24)
632 if seconds:
633 sign = seconds<0 and -1 or 1
634 seconds *= sign
635 S = seconds%60
636 seconds /= 60
637 M = seconds%60
638 seconds /= 60
639 H = seconds%24
640 d = seconds / 24
641 else:
642 months = y*12 + m
643 sign = months<0 and -1 or 1
644 months *= sign
645 m = months%12
646 y = months/12
648 return (sign, y, m, d, H, M, S)
650 class Range:
651 """
652 Represents range between two values
653 Ranges can be created using one of theese two alternative syntaxes:
655 1. Native english syntax:
656 [[From] <value>][ To <value>]
657 Keywords "From" and "To" are case insensitive. Keyword "From" is optional.
659 2. "Geek" syntax:
660 [<value>][; <value>]
662 Either first or second <value> can be omitted in both syntaxes.
664 Examples (consider local time is Sat Mar 8 22:07:48 EET 2003):
665 >>> Range("from 2-12 to 4-2")
666 <Range from 2003-02-12.00:00:00 to 2003-04-02.00:00:00>
668 >>> Range("18:00 TO +2m")
669 <Range from 2003-03-08.18:00:00 to 2003-05-08.20:07:48>
671 >>> Range("12:00")
672 <Range from 2003-03-08.12:00:00 to None>
674 >>> Range("tO +3d")
675 <Range from None to 2003-03-11.20:07:48>
677 >>> Range("2002-11-10; 2002-12-12")
678 <Range from 2002-11-10.00:00:00 to 2002-12-12.00:00:00>
680 >>> Range("; 20:00 +1d")
681 <Range from None to 2003-03-09.20:00:00>
683 """
684 def __init__(self, spec, Type, allow_granularity=1, **params):
685 """Initializes Range of type <Type> from given <spec> string.
687 Sets two properties - from_value and to_value. None assigned to any of
688 this properties means "infinitum" (-infinitum to from_value and
689 +infinitum to to_value)
691 The Type parameter here should be class itself (e.g. Date), not a
692 class instance.
694 """
695 self.range_type = Type
696 re_range = r'(?:^|from(.+?))(?:to(.+?)$|$)'
697 re_geek_range = r'(?:^|(.+?));(?:(.+?)$|$)'
698 # Check which syntax to use
699 if spec.find(';') == -1:
700 # Native english
701 mch_range = re.search(re_range, spec.strip(), re.IGNORECASE)
702 else:
703 # Geek
704 mch_range = re.search(re_geek_range, spec.strip())
705 if mch_range:
706 self.from_value, self.to_value = mch_range.groups()
707 if self.from_value:
708 self.from_value = Type(self.from_value.strip(), **params)
709 if self.to_value:
710 self.to_value = Type(self.to_value.strip(), **params)
711 else:
712 if allow_granularity:
713 self.from_value = Type(spec, **params)
714 self.to_value = Type(spec, add_granularity=1, **params)
715 else:
716 raise ValueError, "Invalid range"
718 def __str__(self):
719 return "from %s to %s" % (self.from_value, self.to_value)
721 def __repr__(self):
722 return "<Range %s>" % self.__str__()
724 def test_range():
725 rspecs = ("from 2-12 to 4-2", "from 18:00 TO +2m", "12:00;", "tO +3d",
726 "2002-11-10; 2002-12-12", "; 20:00 +1d", '2002-10-12')
727 rispecs = ('from -1w 2d 4:32 to 4d', '-2w 1d')
728 for rspec in rspecs:
729 print '>>> Range("%s")' % rspec
730 print `Range(rspec, Date)`
731 print
732 for rspec in rispecs:
733 print '>>> Range("%s")' % rspec
734 print `Range(rspec, Interval)`
735 print
737 def test():
738 intervals = (" 3w 1 d 2:00", " + 2d", "3w")
739 for interval in intervals:
740 print '>>> Interval("%s")'%interval
741 print `Interval(interval)`
743 dates = (".", "2000-06-25.19:34:02", ". + 2d", "1997-04-17", "01-25",
744 "08-13.22:13", "14:25", '2002-12')
745 for date in dates:
746 print '>>> Date("%s")'%date
747 print `Date(date)`
749 sums = ((". + 2d", "3w"), (".", " 3w 1 d 2:00"))
750 for date, interval in sums:
751 print '>>> Date("%s") + Interval("%s")'%(date, interval)
752 print `Date(date) + Interval(interval)`
754 if __name__ == '__main__':
755 test()
757 # vim: set filetype=python ts=4 sw=4 et si