Michael Foord wrote: > Nick Coghlan wrote: >>> Note that using exceptions for control flow can be bad for other >>> implementations of Python. For example exceptions on the .NET framework >>> are very expensive. (Although there are workarounds such as not really >>> raising the exception - but they're ugly). >>> >> >> Is it that exceptions are expensive, or setting up a try/except block is >> expensive? The reason the SkipStatement idea is tenable at all (even in >> CPython) is that try/except is fairly cheap when no exception is raised. >> > > It is the raising of the exception that is expensive.
Then that isn't a huge drawback in this case - the SkipStatement exception is only used in situations which would currently probably be handled by raising an exception anyway (e.g. the change to contextlib.contextmanager.__enter__() in the patch is to raise SkipStatement where it currently raises RuntimeError). Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia --------------------------------------------------------------- _______________________________________________ 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
