Re: Subclassing datetime.date does not seem to work

[Christian Heimes]

Rick King schrieb:

I would like to subclass datetime.date so that I can write:

d = date2('12312008')

I tried:

from datetime import date
class date2(date):
def __init__( self, strng ):
mm,dd,yy = int(strng[:2]), int(strng[2:4]), int(strng[4:])
date.__init__(self,yy,mm,dd)

But then this statement:
d = date2('12312008')

Causes:
TypeError: function takes exactly 3 arguments (1 given)

Is there something basically wrong with subclassing date?
-Rick King

datetime.date is a C extension class. Subclassing of extension classes
may not always work as you'd expect it.

Christian

[John Machin]

On Apr 26, 7:43 am, Christian Heimes <[e-mail]:

Rick King schrieb:

I would like to subclass datetime.date so that I can write:

d = date2('12312008')

I tried:

from datetime import date
class date2(date):
def __init__( self, strng ):
mm,dd,yy = int(strng[:2]), int(strng[2:4]), int(strng[4:])
date.__init__(self,yy,mm,dd)

But then this statement:
d = date2('12312008')

Causes:
TypeError: function takes exactly 3 arguments (1 given)

Is there something basically wrong with subclassing date?
-Rick King

datetime.date is a C extension class. Subclassing of extension classes
may not always work as you'd expect it.

.... and in this case it's a sledgehammer to crack a nut:

>>from datetime import date
def date_from_string(strng):

.... mm, dd, yy = int(strng[:2]), int(strng[2:4]), int(strng[4:])
.... return date(yy, mm, dd)
....

>>date_from_string('12312008')

datetime.date(2008, 12, 31)

>>>

Consider also:

>>import datetime
datetime.datetime.strptime('12312008', '%m%d%Y').date()

datetime.date(2008, 12, 31)