[Python-Dev] Re: 2.2 features

[Guido van Rossum]

> [Guido van Rossum]
> > Marcin 'Qrczak' Kowalczyk <qrczak at knm.org.pl> writes:
> 
> > > Now thow in 'isinstance' as an old way to spell a specific membership
> > > test (for types and classes) which doesn't have to be learned about
> > > at all.
> 
> > I love it.  'x in type' as a shorthand for isinstance(x, type).
> > Checked into CVS!
> 
> The above exchange is dated 2001-07-31, and I'm merely glancing over
> some old saved email.  The above feature does not seem to be implemented
> in Python 2.3.2, as demonstrated by the script below.  Has it been
> retracted?  Not that I really need it, however! :-)

Yes, it was retracted.  From the CVS log the next day:

----------------------------
revision 2.16.8.73
date: 2001/08/01 03:56:39;  author: gvanrossum;  state: Exp;  lines:
+1 -21
Rip out again the 'x in type' support.  Further newsgroup discussion
showed it was confusing.  E.g. people tried "if x in [int, long]:
...".
----------------------------

In retrospect I think it was too cute...

--Guido van Rossum (home page: http://www.python.org/~guido/)