minor #10108 [Routing] Add locale fallback to internationalized routes (Thomas Calvet, javiereguiluz)

This PR was merged into the master branch.

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[Routing] Add locale fallback to internationalized routes

Related PR : symfony/symfony#27957

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02cc739 Minor reword
c15df9d [Routing] Add locale fallback to internationalized routes

Author: javiereguiluz

routing.rst

@@ -214,6 +214,16 @@ should be used during the request. Defining routes this way also eliminated the
 need for duplicate registration of routes which minimizes the risk for any bugs
 caused by definition inconsistency.
 
+.. tip::
+
+    If the application uses full language + territory locales (e.g. ``fr_FR``,
+    ``fr_BE``), you can use the language part only in your routes (e.g. ``fr``).
+    This prevents having to define multiple paths when you want to use the same
+    route path for locales that share the same language.
+
+.. versionadded:: 4.2
+    The feature to fall back on the language part only was introduced in Symfony 4.2.
+
 A common requirement for internationalized applications is to prefix all routes
 with a locale. This can be done by defining a different prefix for each locale
 (and setting an empty prefix for your default locale if you prefer it):