Hello!
Please take a look at the example.
>>> a = [(x, y) for x, y in map(None, range(10), range(10))] # Just a list of
>>> tuples
>>> a
[(0, 0), (1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6), (7, 7), (8,
8), (9, 9)]
Now i want to get a list of functions x*y/n, for each (x, y) in a:
>>> funcs = [lambda n: x * y / n for x, y in a]
It looks consistent!
>>> funcs
[ at 0x010F3DF0>, at 0x010F7CF0>,
at 0x010F7730>, at 0x010FD270>,
at 0x010FD0B0>, at 0x010FD5B0>,
at 0x010FD570>, at 0x010FD630>,
at 0x01100270>, at 0x011002B0>]
...and functions are likely to be different.
>>> funcs[0](1)
81
But they aren't!
>>> for func in funcs:
... print func(1)
...
81
81
81
81
81
81
81
81
81
81
It seems, all functions have x and y set to 9.
What's wrong with it? Is it a bug?
On the other hand, this problem has a solution:
>>> def buldFunc(x, y):
... return lambda n: x * y / n
...
>>> funcs = [buldFunc(x, y) for x, y in a]
... and it does work!
But why not to save several lines of code? ;)
Thanks in advance.
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