Representation of recursive list

[DeaD_EyE]

Guess you have following code:

x = [1, 2, 3]
x.append(x)
print(x)

The output:

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Output:
[1, 2, 3, [...]]

Did you know/expect that?

It's infinite, because it refers on itself.
You can do this:

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def infinite_loop():
    x = [1, 2, 3]
    x.append(x)
    while True:
        x = x[-1]

[snippsat]

Cool not seen that before.
pprint gives some more info.

λ ptpython
>>> from pprint import pprint

>>> x = [1, 2, 3]
>>> x.append(x)
>>> x
[1, 2, 3, [...]]

>>> pprint(x)
[1, 2, 3, <Recursion on list with id=88766544>]

>>> x[-1]
[1, 2, 3, [...]]
>>> x == x[-1]
True