Minor tweaks

Author: javiereguiluz

components/expression_language/syntax.rst

@@ -343,18 +343,23 @@ Ternary Operators
 * ``foo ?: 'no'`` (equal to ``foo ? foo : 'no'``)
 * ``foo ? 'yes'`` (equal to ``foo ? 'yes' : ''``)
 
-Null-coalescing Operator
+Null Coalescing Operator
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
-This is the same as the PHP's null-coalescing operator ``??`` which is a syntactic sugar for the use of a ternary 
-in conjunction with isset(). It returns the left hand-side if it exist and not ``null`` otherwise it returns the right hand-side.
-Note that coalescing can be chained.
+This is the same as the PHP `null-coalescing operator`_, which combines
+the ternary operator and ``isset()``. It returns the left hand-side if it exists
+and it's not ``null``; otherwise it returns the right hand-side. Note that you
+can chain multiple coalescing operators.
 
 * ``foo ?? 'no'``
 * ``foo.baz ?? 'no'``
 * ``foo[3] ?? 'no'``
 * ``foo.baz ?? foo['baz'] ?? 'no'``
 
+.. versionadded:: 6.2
+
+    The null-coalescing operator was introduced in Symfony 6.2.
+
 Built-in Objects and Variables
 ------------------------------
 
@@ -365,3 +370,5 @@ expressions (e.g. the request, the current user, etc.):
 * :doc:`Variables available in security expressions </security/expressions>`;
 * :doc:`Variables available in service container expressions </service_container/expression_language>`;
 * :ref:`Variables available in routing expressions <routing-matching-expressions>`.
+
+.. _`null-coalescing operator`: https://www.php.net/manual/en/language.operators.comparison.php#language.operators.comparison.coalesce