[Tutor] Object defined by initialization parameters ADDITION

[Bob Gailer]

Bob Gailer wrote:
> Andre Engels wrote:
>   
>> Is it possible to define a class in such a way, that if twice an
>> object is made with the same initialization parameters, the same
>> object is returned in both cases?
>>   
>>     
> Use a "factory" function, and store a dictionary of instances as a class 
> property:
>
> class myObj(object):
>   instances = {}
>   def __init__(self,a):
>     # the rest of your code 
>
> def makemyObj(a):
>   if a in myObj.instances:
>     return myObj.instances[a]
>   else:
>     new_instance =  myObj(a)
>     myObj.instances[a] = new_instance 
>     return new_instance 
>  
>   
I neglected to show the function call:

a = makemyObj("a")
b = makemyObj("b")
c = makemyObj("a")

a and c will point to the same object
b will be a different object
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