idiom for initialising variables

[Erik Max Francis]

Trent Mick wrote:

> Despite having a response that looks almost exactly like mine, Erik's
> response reveals a difference that I didn't really identify: that 'a'
> in
> the former case ("TopLevel" in my example) is shared by all instances.
	...
> not-quite-as-swift-as-erik-ly yours,

:-)

There's one significant point that neither of us mentioned, which is
that even when there is a class attribute present, instances _can_
override it locally:

>>> class C:
...  s = 1 # this is the class attribute
...  def __init__(self, x):
...   self.x = x # this is the instance attribute
... 
>>> c1 = C(1)
>>> c2 = C(2)
>>> C.s = 10 # this changes it for all instances
>>> c1.s
10
>>> c2.s
10
>>> c1.s = 20 # but this only changes it for the instance c1
>>> c1.s
20
>>> c2.s
10
>>> C.s
10

-- 
 Erik Max Francis / max at alcyone.com / http://www.alcyone.com/max/
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