Hi everyone, Just stumbled on a fun little thing:
We create a simple structure... l = ([],) Now modify the list, and... l[0] += [1] ...we fail: ## Traceback (most recent call last): ## File "F:\work\ImageGrid\cur\ImageGrid\src\test\python-bug.py", line 17, in <module> ## l[0] += [1] ## TypeError: 'tuple' object does not support item assignment Tested on 2.5, 2.7, 3.1, PyPy1.8 on win32 and 2.7 on x86-64 Debian (just in case). I was expecting this to succeed, is this picture wrong or am I missing something? ...am I really the first one to try and modify a list within a tuple directly?! It's even more odd that I did not try this myself since first started with Python back in 99 :) I could not google this "feature" out either... BTW, It is quite trivial (and obvious) to trick the interpreter to get the desired result... e = l[0] e += [1] P.S. the attachment is runnable version of the above code... -- Thanks! Alex. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
