gh-69619: Define whitespace for str.lstrip() and str.rstrip()

kyo5uke · kyo5uke · commit 19b8f3022039 · 2026-06-04T02:14:11.000+09:00
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
@@ -2377,7 +2377,11 @@ expression support in the :mod:`re` module).
    Return a copy of the string with leading characters removed.  The *chars*
    argument is a string specifying the set of characters to be removed.  If omitted
    or ``None``, the *chars* argument defaults to removing whitespace.  The *chars*
-   argument is not a prefix; rather, all combinations of its values are stripped::
+   argument is not a prefix; rather, all combinations of its values are stripped.
+
+   Whitespace characters are defined by :meth:`str.isspace`.
+
+   For example::
 
       >>> '   spacious   '.lstrip()
       'spacious   '
@@ -2581,6 +2585,9 @@ expression support in the :mod:`re` module).
    argument is a string specifying the set of characters to be removed.  If omitted
    or ``None``, the *chars* argument defaults to removing whitespace.  The *chars*
    argument is not a suffix; rather, all combinations of its values are stripped.
+
+   Whitespace characters are defined by :meth:`str.isspace`.
+
    For example:
 
    .. doctest::
