Original code copyright (C) 2009-2022 Rudolf Cardinal (

This file is part of cardinal_pythonlib.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

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Support functions for sorting.

class cardinal_pythonlib.sort.MinType[source]

An object that compares less than anything else.

cardinal_pythonlib.sort.atoi(text: str) int | str[source]

Converts strings to integers if they’re composed of digits; otherwise returns the strings unchanged. One way of sorting strings with numbers; it will mean that "11" is more than "2".

class cardinal_pythonlib.sort.attrgetter_nonesort(attr, *attrs)[source]

Modification of operator.attrgetter. Returns an object’s attributes, or the mintype_singleton if the attribute is None.

class cardinal_pythonlib.sort.methodcaller_nonesort(**kwargs)[source]

As per attrgetter_nonesort (q.v.), but for methodcaller.

cardinal_pythonlib.sort.natural_keys(text: str) List[int | str][source]

Sort key function. Returns text split into string/number parts, for natural sorting; as per

Example (as per the source above):

>>> from cardinal_pythonlib.sort import natural_keys
>>> alist=[
...     "something1",
...     "something12",
...     "something17",
...     "something2",
...     "something25",
...     "something29"
... ]
>>> alist.sort(key=natural_keys)
>>> alist
['something1', 'something2', 'something12', 'something17', 'something25', 'something29']