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| From | Terry Reedy <tjreedy@udel.edu> |
| Subject | Re: root[:]=[root,root] |
| Date | Sat, 17 Dec 2011 22:08:24 -0500 |
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On 12/16/2011 9:40 PM, YAN HUA wrote: > Hi,all. Could anybody tell how this code works? > >>> root = [None, None] > >>> root[:] = [root, root] > >>> root > [[...], [...]] > >>> root[0] > [[...], [...]] > >>> root[0][0][1][1][0][0][0][1][1] > [[...], [...]] A simpler example: >>> l = [] >>> l.append(l) >>> l [[...]] Python is (now) smart enough to recognize a recursive list and print '...' instead of going into an infinite loop printing '['s (as it once did, I believe). -- Terry Jan Reedy
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Re: root[:]=[root,root] Terry Reedy <tjreedy@udel.edu> - 2011-12-17 22:08 -0500
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