> trunc() has well-defined semantics -- it takes a Real instance and > converts it to an Integer instance using round-towards-zero semantics.
No. trunc calls __trunc__, which does whatever it pleases to do. >>> class A: ... def __trunc__(self): ... return 0 ... >>> a=A() >>> trunc(a) 0 > > int() has undefined semantics -- it takes any object and converts it > to an int (a concrete type!) using whatever rules it likes -- the > definition of __int__ is up to whatever the source type likes to do. > For float this has been defined the same as trunc() above, but for > other types, who knows! int() of a string does something completely > different. But why is that a reason to keep trunc()? If you only ever want to convert floats to ints, you can use either one, with no difference. int() does *not* have undefined semantics, for floats, it converts it to an integer using round-towards-zero semantics. Regards, Martin _______________________________________________ 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
