On Wed, 13 Mar 2013, Oscar Benjamin wrote:
(it's not actually a generator by the way)
As Oscar points out, you're not working with a generator expression. The
syntactical difference between a list comprehension and a generator
expression is subtle. List comprehensions use square brackets, but
generator expressions use parentheses.
foo = [n for n in xrange(10)]
foo
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
bar = (n for n in xrange(10))
bar
<generator object at 0xb7eaadec>
FWIW, if you're working with very large lists, but don't need to create
the full list in memory, then a generator expression is usually preferred.
To get the number of items a generator would return, you can use sum()
like this:
gen = (n for n in xrange(some_really_huge_number))
sum(1 for n in gen) # outputs some_really_huge_number
--dk.
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