[Python-Dev] Sets: elt in dict, lst.include - really begs for a PEP

[Skip Montanaro]

After reading through this thread and noticing (but not paying close
attention to) all the related posts on c.l.py (subject: "in for dicts"), it
seems to me that the whole "if/for something in dict" thing needds to be
hashed out in a PEP.  There were a fair amount of "Python's changing too
fast" rants when 2.0 was released.  Adding a major feature such as this at
the 2.1 stage is only going to generate that many more rants.  The fact that
it was easy for Thomas to implement "if key in dict" doesn't make the
overall concept less controversial.  There are apparently lots of varying
opinions about what's reasonable.  This topic seems related to PEP 212 (Loop
Counter Iteration) and PEP 218 (Adding a Built-In Set Object Type), but may
well warrant its own.

That said, I have plenty enough on my plate trying to keep Mojam afloat
these days, so I can't step into the crevass, just observe that it looks to
me like a very long ways to the bottom... ;-)

Skip