# Date objects support one visible method, date.weekday(). This returns
# the day of the week the date falls on, as a string.
#
-# Date objects also have 4 (conceptually) read-only data attributes:
+# Date objects also have 4 read-only data attributes:
# .month in 1..12
# .day in 1..31
# .year int or long int
# Tim Peters tim@ksr.com
# not speaking for Kendall Square Research Corp
+# Adapted to Python 1.1 (where some hacks to overcome coercion are unnecessary)
+# by Guido van Rossum
+
+# vi:set tabsize=8:
+
_MONTH_NAMES = [ 'January', 'February', 'March', 'April', 'May',
'June', 'July', 'August', 'September', 'October',
'November', 'December' ]
raise TypeError, 'argument must be integer: ' + `type(n)`
ans = Date(1,1,1) # arguments irrelevant; just getting a Date obj
+ del ans.ord, ans.month, ans.day, ans.year # un-initialize it
ans.ord = n
n400 = (n-1)/_DI400Y # # of 400-year blocks preceding
year, n = year + more, int(n - dby)
try: year = int(year) # chop to int, if it fits
- except ValueError: pass
+ except (ValueError, OverflowError): pass
month = min( n/29 + 1, 12 )
dbm = _days_before_month( month, year )
self.month, self.day, self.year = month, day, year
self.ord = _date2num( self )
+ # don't allow setting existing attributes
+ def __setattr__( self, name, value ):
+ if self.__dict__.has_key(name):
+ raise AttributeError, 'read-only attribute ' + name
+ self.__dict__[name] = value
+
def __cmp__( self, other ):
return cmp( self.ord, other.ord )
self.day,
_MONTH_NAMES[self.month-1] ) + `self.year`
- # automatic coercion is a pain for date arithmetic, since e.g.
- # date-date and date-int mean different things. So, in order to
- # sneak integers past Python's coercion rules without losing the info
- # that they're really integers (& not dates!), integers are disguised
- # as instances of the derived class _DisguisedInt. That this works
- # relies on undocumented behavior of Python's coercion rules.
- def __coerce__( self, other ):
- if type(other) in _INT_TYPES:
- return self, _DisguisedInt(other)
- # if another Date, fine
- if type(other) is type(self) and other.__class__ is Date:
- return self, other
-
- # Python coerces int+date, but not date+int; in the former case,
- # _DisguisedInt.__add__ handles it, so we only need to do
- # date+int here
+ # Python 1.1 coerces neither int+date nor date+int
def __add__( self, n ):
if type(n) not in _INT_TYPES:
raise TypeError, 'can\'t add ' + `type(n)` + ' to date'
return _num2date( self.ord + n )
+ __radd__ = __add__ # handle int+date
- # Python coerces all of int-date, date-int and date-date; the first
- # case winds up in _DisguisedInt.__sub__, leaving the latter two
- # for us
+ # Python 1.1 coerces neither date-int nor date-date
def __sub__( self, other ):
- if other.__class__ is _DisguisedInt: # date-int
- return _num2date( self.ord - other.ord )
+ if type(other) in _INT_TYPES: # date-int
+ return _num2date( self.ord - other )
else:
return self.ord - other.ord # date-date
- def weekday( self ):
- return _num2day( self.ord )
-
-# see comments before Date.__add__
-class _DisguisedInt( Date ):
- def __init__( self, n ):
- self.ord = n
-
- # handle int+date
- def __add__( self, other ):
- return other.__add__( self.ord )
-
# complain about int-date
- def __sub__( self, other ):
+ def __rsub__( self, other ):
raise TypeError, 'Can\'t subtract date from integer'
+ def weekday( self ):
+ return _num2day( self.ord )
+
def today():
import time
local = time.localtime(time.time())
b = Date(9,30,1914)
if `a` != 'Tue 30 Sep 1913':
raise DateTestError, '__repr__ failure'
- if (not a < b) or a == b or a > b or b != b or \
- a != 698982 or 698982 != a or \
- (not a > 5) or (not 5 < a):
+ if (not a < b) or a == b or a > b or b != b:
raise DateTestError, '__cmp__ failure'
if a+365 != b or 365+a != b:
raise DateTestError, '__add__ failure'
# Rational numbers
+from types import *
def rat(num, den):
+ if type(num) == FloatType or type(den) == FloatType:
+ return num/den
return Rat(num, den)
def __init__(self, num, den):
if den == 0:
raise ZeroDivisionError, 'rat(x, 0)'
- g = gcd(num, den)
+ if type(den) == FloatType or type(num) == FloatType:
+ g = float(den)
+ else:
+ g = gcd(num, den)
self.num = num/g
self.den = den/g
def __repr__(self):
- return 'rat' + `self.num, self.den`
+ return 'Rat(%s, %s)' % (self.num, self.den)
+
+ def __str__(self):
+ if self.den == 1:
+ return str(self.num)
+ else:
+ return '%s/%s' % (self.num, self.den)
def __cmp__(a, b):
c = a-b
def __coerce__(a, b):
t = type(b)
- if t == type(0):
- return a, rat(b, 1)
- if t == type(0L):
- return a, rat(b, 1L)
- if t == type(0.0):
- return a.__float__(), b
- if t == type(a) and a.__class__ == b.__class__:
+ if t == IntType:
+ return a, Rat(b, 1)
+ if t == LongType:
+ return a, Rat(b, 1L)
+ if t == FloatType:
+ return a, Rat(b, 1.0)
+ if t == InstanceType and a.__class__ == b.__class__:
return a, b
raise TypeError, 'Rat.__coerce__: bad other arg'
def __add__(a, b):
- if type(b) <> type(a):
- a, b = a.__coerce__(b)
- return a + b
return rat(a.num*b.den + b.num*a.den, a.den*b.den)
def __sub__(a, b):
return rat(a.num*b.den - b.num*a.den, a.den*b.den)
def __mul__(a, b):
- if type(b) <> type(a):
- a, b = a.__coerce__(b)
- return a * b
return rat(a.num*b.num, a.den*b.den)
def __div__(a, b):
def test():
- print rat(-1L, 1)
- print rat(1, -1)
- a = rat(1, 10)
+ print Rat(-1L, 1)
+ print Rat(1, -1)
+ a = Rat(1, 10)
print int(a), long(a), float(a)
- b = rat(2, 5)
+ b = Rat(2, 5)
l = [a+b, a-b, a*b, a/b]
print l
l.sort()
print l
- print rat(0, 1)
+ print Rat(0, 1)
print a+1
print a+1L
print a+1.0
try:
- print rat(1, 0)
+ print Rat(1, 0)
raise SystemError, 'should have been ZeroDivisionError'
except ZeroDivisionError:
print 'OK'
projects / thirdparty / Python / cpython.git / commitdiff
