George Sakkis wrote: > "Steven Bethard" <[EMAIL PROTECTED]> wrote: >> Dict comprehensions were recently rejected: >> http://www.python.org/peps/pep-0274.html >> The reason, of course, is that dict comprehensions don't gain you >> much at all over the dict() constructor plus a generator expression, >> e.g.: >> dict((i, chr(65+i)) for i in range(4)) > > Sure, but the same holds for list comprehensions: list(i*i for i in > xrange(10)). The difference is historic I guess; list comprehensions > preceded generator expressions and so they cannot be removed, at least > not before 3.0. I wonder if they will/should be in the language when > the constraint of backwards compatibility is lifted. IMO they should > not (TIOOWTDI, uniformity among builtin data structures, not > overwhelmingly more useful than set or dict comprehensions), but > there's a long way till that day.
I think the jury's still out on this one: * Alex Martelli expects list comprehensions to be removed. [1] * Robert Kern wants list comprehensions removed. [2] * Raymond Hettinger encourages continued use of list comprehensions [3] * Jeremy Bowers thinks list comprehensions should stay. [4] I only searched a few relatively recent threads in c.l.py, so there are probably more, but it looks to me like the final decision will have to be made by a pronouncement from Guido. [1]http://groups-beta.google.com/group/comp.lang.python/msg/f5613c00cb8c9539 [2]http://groups-beta.google.com/group/comp.lang.python/msg/b2cf0cd72d53fbe5 [3]http://groups-beta.google.com/group/comp.lang.python/msg/781dfab03701dd18 [4]http://groups-beta.google.com/group/comp.lang.python/msg/771a47d9eb24c863 -- http://mail.python.org/mailman/listinfo/python-list
