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How to check if list is nested?

How to check if list is nested?

How to check if list is nested?


How can I check if some list is nested?
I have a list:


mylist = ['a', 'b', 'c']
then I make a change:


mylist[0] = ('a1', 'a2')
Now I have nested list:


[('a1', 'a2'),'b', 'c']
When I want to loop through mylist and print it, I need to check somehow if some list index is nested or not because if yes, printing will be different for nested indexes.



RE: How to check if list is nested?

First off, a small nitpick: the square brackets [] are for lists, but the round brackets () are for tuples. As I understand it, tuples are immutable (cannot have their content or structure changed). I bring it up because it affects your solution slightly:


$ python
Python 2.5.1 (r251:54863, May  2 2007, 16:56:35)
[GCC 4.1.2 (Ubuntu 4.1.2-0ubuntu4)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> mylist = ['a', 'b', 'c']
>>> mylist[0] = ('a1', 'a2')
>>> mylist
[('a1', 'a2'), 'b', 'c']
>>> if (type(mylist[0]) == tuple):
...     print "do tuple logic"
... elif (type(mylist[0]) == list):
...     print "do list logic"
... else:
...     print "do something else"
do tuple logic

I don't know enough about python to know if this is good form or not, but it does work.

RE: How to check if list is nested?


This seems to be simplest and shortest way.


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