get a self data in a method call

[David Abrahams]

polux <polux2001 at wanadoo.fr> writes:

> I've a class
>
> class MyClass:
> 	
> 	def __init__(self):
> 		self.data = 123
>
>
> now, I want to define a method, which would be like that if it were
> possible :
>
> 	def func(self, data = self.data )
>
> but it doesn't work because python does't know yet what "self" is

The typical solution is something like this:

       def func(self, data = None):
           if data is None:
              data = self.data

If self.data can be None, then make up some private object whose
purpose is to denote "unspecified", and substitute that for None.


-- 
                       David Abrahams
   dave at boost-consulting.com * http://www.boost-consulting.com
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