[issue9982] Pointer problem in initializing array of arrays

[Antoine Pitrou]

Antoine Pitrou <pitrou at free.fr> added the comment:

That's expected behaviour, syntactically. Multiplying a sequence doesn't deep-copy its elements.
If you want an array of distinct arrays, just write:

>>> m1 = [[0,0,0,0] for i in range(4)]
>>> m1[1][0] = 6
>>> m1
[[0, 0, 0, 0], [6, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]

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nosy: +pitrou
resolution:  -> invalid
status: open -> closed

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue9982>
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