different binding behavior

[David Wahler]

Gabriel Zachmann wrote:
> It seems to me that the following behavior of python (2.4.1) is inconsistent:
[snip]
> Why was it implemented like this??

Lists are mutable objects; integers are not. For a list, a += b is
equivalent to a.__iadd__(b), which is an in-place modification.

For an integer, no __iadd__ method is provided, so a += b is equivalent
to a = a.__add__(b), which is a rebinding operation rather than a
modification.

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-- David