SV: Polymorphism using constructors

[K Viltersten]

"Diez B. Roggisch" <deets at nospam.web.de> skrev i meddelandet 
news:63346uF25gigqU1 at mid.uni-berlin.de...
>K Viltersten schrieb:
>> I'm writing a class for rational numbers
>> and besides the most obvious constructor
>>
>>  def __init__ (self, nomin, denom):
>>
>> i also wish to have two supporting ones
>>
>>  def __init__ (self, integ):
>>    self.__init__ (integ, 1)
>>  def __init__ (self):
>>    self.__init__ (0, 1)
>>
>> but for some reason (not known to me at
>> this point) i get errors. My suspicion is that it's a syntax issue.
>
> "errors" is not much of an error-description. That's what stacktraces are 
> for.

I assumed that the error was so obvious to a
seasoned Pytonist (Pythoner?) that a trace
didn't matter. Your help below proves it. :)

Nevertheless, i'll be careful in the future
and make sure to post the traces too. Sorry.

> Apart from that, you won't succeed with the above. Python has no 
> signature-based polymorphism. Instead, you use default arguments, like 
> this:
>
> def __init__(nomin=0, denom=1):
>     ...

Thank you.

--
Regards
Konrad Viltersten
--------------------------------
sleep    - a substitute for coffee for the poor
ambition - lack of sense to be lazy