#16523: improve attrgetter/itemgetter/methodcaller documentation.
diff --git a/Doc/library/operator.rst b/Doc/library/operator.rst
index 3860880..de7a542 100644
--- a/Doc/library/operator.rst
+++ b/Doc/library/operator.rst
@@ -241,13 +241,22 @@
expect a function argument.
-.. function:: attrgetter(attr[, args...])
+.. function:: attrgetter(attr)
+ attrgetter(*attrs)
- Return a callable object that fetches *attr* from its operand. If more than one
- attribute is requested, returns a tuple of attributes. After,
- ``f = attrgetter('name')``, the call ``f(b)`` returns ``b.name``. After,
- ``f = attrgetter('name', 'date')``, the call ``f(b)`` returns ``(b.name,
- b.date)``. Equivalent to::
+ Return a callable object that fetches *attr* from its operand.
+ If more than one attribute is requested, returns a tuple of attributes.
+ The attribute names can also contain dots. For example:
+
+ * After ``f = attrgetter('name')``, the call ``f(b)`` returns ``b.name``.
+
+ * After ``f = attrgetter('name', 'date')``, the call ``f(b)`` returns
+ ``(b.name, b.date)``.
+
+ * After ``f = attrgetter('name.first', 'name.last')``, the call ``f(b)``
+ returns ``(r.name.first, r.name.last)``.
+
+ Equivalent to::
def attrgetter(*items):
if any(not isinstance(item, str) for item in items):
@@ -267,14 +276,19 @@
return obj
- The attribute names can also contain dots; after ``f = attrgetter('date.month')``,
- the call ``f(b)`` returns ``b.date.month``.
-
-.. function:: itemgetter(item[, args...])
+.. function:: itemgetter(item)
+ itemgetter(*items)
Return a callable object that fetches *item* from its operand using the
operand's :meth:`__getitem__` method. If multiple items are specified,
- returns a tuple of lookup values. Equivalent to::
+ returns a tuple of lookup values. For example:
+
+ * After ``f = itemgetter(2)``, the call ``f(r)`` returns ``r[2]``.
+
+ * After ``g = itemgetter(2, 5, 3)``, the call ``g(r)`` returns
+ ``(r[2], r[5], r[3])``.
+
+ Equivalent to::
def itemgetter(*items):
if len(items) == 1:
@@ -313,9 +327,14 @@
Return a callable object that calls the method *name* on its operand. If
additional arguments and/or keyword arguments are given, they will be given
- to the method as well. After ``f = methodcaller('name')``, the call ``f(b)``
- returns ``b.name()``. After ``f = methodcaller('name', 'foo', bar=1)``, the
- call ``f(b)`` returns ``b.name('foo', bar=1)``. Equivalent to::
+ to the method as well. For example:
+
+ * After ``f = methodcaller('name')``, the call ``f(b)`` returns ``b.name()``.
+
+ * After ``f = methodcaller('name', 'foo', bar=1)``, the call ``f(b)``
+ returns ``b.name('foo', bar=1)``.
+
+ Equivalent to::
def methodcaller(name, *args, **kwargs):
def caller(obj):