2009/4/7 Cesare Di Mauro <cesare.dima...@a-tono.com>: > The principle that I followed on doing constant folding was: "do what Python > will do without constant folding enabled". > > So if Python will generate > > LOAD_CONST 1 > LOAD_CONST 2 > BINARY_ADD > > the constant folding code will simply replace them with a single > > LOAD_CONST 3 > > When working with such kind of optimizations, the temptation is to > apply them at any situation possible. For example, in other languages > this > > a = b * 2 * 3 > > will be replaced by > > a = b * 6 > > In Python I can't do that, because b can be an object which overloaded > the * operator, so it *must* be called two times, one for 2 and one for 3. > > That's the way I choose to implement constant folding.
That sounds sufficiently "super risk-averse" to me, so I'm in favour of constant folding being implemented with this attitude :-) Paul. _______________________________________________ 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
