PEP 257: Use sys.maxsize

[pankwings]

In python3, sys.maxint changed to sys.maxsize.

[cpython-cla-bot]

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[Rosuav]

Hmm, I'm not sure that that's accurate - sys.maxsize is the maximum size of a container, which might not be the same as maxint (Python 2 had both). Python 3 simply doesn't have a maximum integer, so the idea of setting one doesn't really make sense now. Maybe it would be better to use None, or float("inf")?

[pankwings]

Thank you for the response. These are my observations:
For python3:

❯ python3
Python 3.8.10 (default, Mar 15 2022, 12:22:08) 
[GCC 9.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.maxint
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module 'sys' has no attribute 'maxint'
>>> sys.maxsize
9223372036854775807
>>>

For python2

❯ python
Python 2.7.18 (default, Mar  8 2021, 13:02:45) 
[GCC 9.3.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> indent = sys.maxint
>>> sys.maxint
9223372036854775807
>>> 

The sys.maxsize in python3 and sys.maxint in python2 within the same machine can be interchangeably used as both returns the same value 9223372036854775807.

[Rosuav]

It so happens that, on your version of Python (and mine), Py2's maxint and maxsize are the same number as Py3's maxsize. Is it actually true that they are interchangeable though?

Another consideration might be that, since this is talking about indentation, a "stupidly big" value might be sufficient. For instance, 1<<100 is going to be way bigger than any sane indentation size, yet it's independent of machine-specific sizes.

Hard to say which is best - float("inf"), 1<<100, None (the latter truly giving a sentinel value, which is the purpose here, but that requires changing the condition slightly). I think possibly None is the best option here, but it's arguable.

[AA-Turner]

Sphinx uses sys.maxsize [1]. I tried locally with an indent of 1,000,000,000 spaces (for a ~950MB file) and the Python interpreter didn't crash -- I'd test further but I don't have 1TB free (or several hours to wait for the completion. I think using sys.maxsize is the most pragmatic reinterpretation of the original intent, although I see Chris' point that maxsize isn't quite the same as maxint.

A

[1] https://github.com/sphinx-doc/sphinx/blob/v5.0.1/sphinx/util/docstrings.py#L60-L71

[pankwings]

Yes, it seems like both are different in different versions of python. Here is the one difference I have observed between python2 and python3:

python2

Python 2.7.18 (default, Mar  8 2021, 13:02:45) 
[GCC 9.3.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> print(type(sys.maxsize))
<type 'int'>
>>> print(type(sys.maxint))
<type 'int'>

In python version 2, type 'int' is the type obtained.

python3

Python 3.8.10 (default, Mar 15 2022, 12:22:08) 
[GCC 9.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> print(type(sys.maxsize))
<class 'int'>

In python version 3, class 'int' is the type obtained.