On Fri, Mar 19, 2010 at 5:50 PM, Guido van Rossum <gu...@python.org> wrote:
> As a downside, there is the worry that inadvertent mixing of Decimal > and float can compromise the correctness of programs in a way that is > hard to detect. But the anomalies above indicate that not fixing the Decimal already has something that we can use in this case, and fits very nice here: Signals. Signals represent conditions that arise during computation. Each corresponds to one context flag and one context trap enabler. So, if we add a signal like "MixedWithFloats", users will have a flag in the context that they could check to see if a float was mixed in the operations executed (and if the user set the trap accordingly, an exception will be raised when the signal happens). OTOH, returning a float the first time both are mixed is easy to check... but if it has downsides, and we prefer to return a Decimal in that case, note that we have a mechanism in Decimal we can use. Furthermore, in case we want to ease the transition we can do the following: - add this signal - set *by default* the trap to raise an exception when float and Decimal is mixed So, the behaviour will be the same as we have now, but users can easily change it. Regards, -- . Facundo Blog: http://www.taniquetil.com.ar/plog/ PyAr: http://www.python.org/ar/ _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com