Extending: overloading operators (e.g. for a vector class)

[Chris Liechti]

thank you Greg and Bernhard. i'll try that

can you give me a hint where such thing as the NEW_STYLE_NUMBER flags are 
documented?

chris

Greg Ewing <look at replyto.address.invalid> wrote in 
news:3CEC5A54.F6EA2C82 at replyto.address.invalid:
> Chris Liechti wrote:
>> 
>> it seems to me tp_as_number supports __mul__ for numbers, but only for
>> instances of the same type, 
> 
> Looking at the interpreter code, it looks like if you set
> the NEW_STYLE_NUMBER flag in the type object, the object's
> binary operator methods are called directly, regardless of
> the other operand type, and without any coercion.
> 
>> and there seems so be an other place where a __mul__ can be emulated:
>> sq_repeat for sequences. can/must i define both, or none?
> 
> It also seems that the sq_repeat slot is never called
> from interpreted code any more.
> 
> So, it appears that if you:
> 
>    1) set the NEW_STYLE_NUMBER flag
>    2) put your method in the tp_as_number->nb_multiply slot
> 
> you will get the same result as you did with the
> Python version.
> 



-- 
Chris <cliechti at gmx.net>