In all probability, both list comprehensions and generator expressions will be around in perpetuity. List comps have been a very successful language feature.
The root of this discussion has been the observation that a list comprehension can be expressed in terms of list() and a generator expression. However, the former is faster when you actually want a list result and many people (including Guido) like the square brackets. After the advent of generators, it seemed for a while that all functions and methods that returned lists would eventually return iterators instead. What we are learning is that there is a place for both. It is darned inconvenient to get an iterator when you really need a list, when you want to slice the result, when you want to see a few elements through repr(), and when you need to loop over the contents more than once. Raymond Hettinger -- http://mail.python.org/mailman/listinfo/python-list
