On Mar 19, 2010, at 4:50 AM, Antoine Pitrou wrote: > Glenn Linderman <glenn <at> nevcal.com> writes: >> >> On the other hand, if the default behavior is to do an implicit >> conversion, I don't know of any way that that could be turned into an >> exception for those coders that don't want or don't like the particular >> type of implicit conversion chosen. > > You still haven't given a good reason why we should raise an exception rather > than do a comparison, though. > > The fact that some particular coders don't like "the particular type of > implicit > conversion chosen" is a particularly weak argument. Python isn't a language > construction framework; we try to choose useful defaults rather than simply > give > out a box of tools. If some people don't like the defaults (significant > indentation, limitless precision integers, etc.), there are other choices out > there.
The reason to prefer an exception is that decimal/float comparisons are more likely to be a programmer error than an intended behavior. Real use cases for decimal/float comparisons are rare and would be more clearly expressed with an explicit conversion using Decimal.from_float(). Of course there is a precedent, I can compare "120" < 140 in AWK and get an automatic implicit conversion ;-) Just because we can compare, doesn't mean we should. Raymond _______________________________________________ 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
