[Python-Dev] yield without future statement?

Jeremy Hylton jeremy@zope.com
Mon, 13 Aug 2001 12:24:02 -0400 (EDT)

>>>>> "GvR" == Guido van Rossum <guido@python.org> writes:

  GvR> On c.l.py, there's a small discussion going on the necessity of
  GvR> a future statement to enable the yield keyword.  The general
  GvR> opinion seems to be that the future statement is redundant,
  GvR> since previous uses of yield will generally result in a syntax
  GvR> error -- and there aren't very many uses of yield in the first
  GvR> place.  The other uses of future (nested scopes and division)
  GvR> were needed because these features cause *silent* failure --
  GvR> but with yield, you'd have to work really really hard to cause
  GvR> a silent failure.

I does seem almost comical that the introduction of yield as a keyword
requires a future statement but the descr branch changes do not.  Talk
about silent failures -- dir() no longers work, method resolution for
multiple inheritance changes, changes to the str names of types.  Why
don't these require a future statement?