minor #17797 [ExpressionLanguage] Deprecate loose comparisons when using the "in" operator (alexandre-daubois)

This PR was merged into the 6.3 branch.

Discussion
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[ExpressionLanguage] Deprecate loose comparisons when using the "in" operator

Fixes #17796

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296a5be [ExpressionLanguage] Deprecate loose comparisons when using the "in" operator

Author: javiereguiluz

components/expression_language.rst

@@ -432,6 +432,13 @@ For example::
 
 The ``$inGroup`` would evaluate to ``true``.
 
+.. deprecated:: 6.3
+
+    In Symfony versions previous to 6.3, ``in`` and ``not in`` operators
+    were using loose comparison. Using these operators with variables of
+    different types is now deprecated, and these operators will be using
+    strict comparison from Symfony 7.0.
+
 Numeric Operators
 .................