minor #4510 [Doc] Update the docs about attribute() function (javiere…

…guiluz)

This PR was squashed before being merged into the 3.x branch.

Discussion
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[Doc] Update the docs about attribute() function

I Was fixing `filter` -> `function` error, but I realized that we could expand the docs of `attribute()` a bit, even if it's deprecated 🙏

Commits
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84daad9 [Doc] Update the docs about attribute() function

doc/functions/attribute.rst

@@ -3,21 +3,30 @@
 
 .. warning::
 
-    The ``attribute`` filter is deprecated as of Twig 3.15. Use the
+    The ``attribute`` function is deprecated as of Twig 3.15. Use the
     :ref:`dot operator <dot_operator>` that now accepts any expression
     when wrapped with parenthesis.
 
-    Note that this filter will still be available in Twig 4.0 to allow a
+    Note that this function will still be available in Twig 4.0 to allow a
     smoother upgrade path.
 
-The ``attribute`` function can be used to access a "dynamic" attribute of a
-variable:
+The ``attribute`` function lets you access an attribute, method, or property of
+an object or array when the name of that attribute, method, or property is stored
+in a variable or dynamically generated with an expression:
 
 .. code-block:: twig
 
-    {{ attribute(object, method) }}
-    {{ attribute(object, method, arguments) }}
-    {{ attribute(array, item) }}
+    {# method_name is a variable that stores the method to call #}
+    {{ attribute(object, method_name) }}
+
+    {# you can also pass arguments when calling a method #}
+    {{ attribute(object, method_name, arguments) }}
+
+    {# the method/property name can be the result of evaluating an expression #}
+    {{ attribute(object, 'some_property_' ~ user.type) }}
+
+    {# in addition to objects, this function works with plain arrays as well #}
+    {{ attribute(array, item_name) }}
 
 In addition, the ``defined`` test can check for the existence of a dynamic
 attribute:
@@ -29,7 +38,7 @@ attribute:
 .. note::
 
     The resolution algorithm is the same as the one used for the ``.``
-    operator, except that the item can be any valid expression.
+    operator.
 
 Arguments
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