Floating point bug?

[Jeff Schwab]

Christian Heimes wrote:
> Dennis Lee Bieber wrote:
>> 	What's wrong with just
>>
>> 	str(0.3)
>>
>> that's what "print" invokes, whereas the interpreter prompt is using 
>>
>> 	repr(0.3)
>>
> 
> No, print invokes the tp_print slot of the float type. Some core types
> have a special handler for print. The tp_print slot is not available
> from Python code and most people don't know about it. :]

Why does print use the tp_print slot, rather than str()?  Are the two 
effectively redundant?  If (non-repr) string representations are 
frequently needed for a given type, could str() be implemented as a 
reference to tp_slot, via a C-language extension?