Deprecate type 'identity'.

diff --git a/include/deal.II/base/template_constraints.h b/include/deal.II/base/template_constraints.h
index 3f5f3ae36b0c069edddf07f8ae1595cc3ad3942f..31e7f5a47f05ba1fd21d80228951f4c7aab5a1f1 100644 (file)
--- a/include/deal.II/base/template_constraints.h
+++ b/include/deal.II/base/template_constraints.h
@@ -342,7 +342,7 @@ constexpr bool has_begin_and_end =
  * @deprecated Use `std_cxx20::identity_type` instead.
  */
 template <typename T>
-using identity = std_cxx20::type_identity<T>;
+using identity DEAL_II_DEPRECATED_EARLY = std_cxx20::type_identity<T>;
 
 
 /**