gh-133986: Document string split algorithm when sep is None and maxsplit is 0 (#133987)

tml · nedbat · donbarbos · web-flow · commit 3e23047363f3 · 2025-05-14T06:17:26.000-04:00
* Document string split algorithm when sep is None and maxsplit is 0

* Update Doc/library/stdtypes.rst

Co-authored-by: Semyon Moroz &lt;donbarbos@proton.me&gt;

---------

Co-authored-by: Ned Batchelder &lt;ned@nedbatchelder.com&gt;
Co-authored-by: Semyon Moroz &lt;donbarbos@proton.me&gt;
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
@@ -2269,6 +2269,18 @@ expression support in the :mod:`re` module).
       >>> '   1   2   3   '.split()
       ['1', '2', '3']
 
+   If *sep* is not specified or is ``None`` and  *maxsplit* is ``0``, only
+   leading runs of consecutive whitespace are considered.
+
+   For example::
+
+      >>> "".split(None, 0)
+      []
+      >>> "   ".split(None, 0)
+      []
+      >>> "   foo   ".split(maxsplit=0)
+      ['foo   ']
+
 
 .. index::
    single: universal newlines; str.splitlines method
