Infinitely nested containers

Steven D'Aprano steve+comp.lang.python at
Sun Nov 23 06:59:00 CET 2014

Ethan Furman wrote:

> On 11/21/2014 08:43 PM, Steven D'Aprano wrote:
>> random832 at wrote:
>>> I think I tried on at least one python version and printing the tuple
>>> crashed with a recursion depth error, since it had no special protection
>>> for this case the way list printing does.
>> It works fine now (Python 3.3).
>> py> L = []
>> py> t = (L, None)
>> py> L.append(L)
>> py> L.append(t)  # For good measure.
>> py> print(t)
>> ([[...], (...)], None)
> This is a tuple in a list in a tuple, not a tuple in a tuple.

Really? I hadn't noticed.


It's still a tuple in itself, recursively, and the tuple to str conversion
routine still has to deal with the fact.


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