diff --git a/examples/xtd.core.examples/exceptions/user_defined_exception/src/user_defined_exception.cpp b/examples/xtd.core.examples/exceptions/user_defined_exception/src/user_defined_exception.cpp
index 1c96ffd100c..5376c0bdca4 100644
--- a/examples/xtd.core.examples/exceptions/user_defined_exception/src/user_defined_exception.cpp
+++ b/examples/xtd.core.examples/exceptions/user_defined_exception/src/user_defined_exception.cpp
@@ -7,14 +7,14 @@ using namespace xtd::diagnostics;
 namespace user_defined_exception {
   class employee_list_not_found_exception : public exception {
   public:
-    employee_list_not_found_exception(const stack_frame& sf = stack_frame::current()) : exception {"The employee list does not exist."_t, sf} {
+    employee_list_not_found_exception(const stack_frame& frame = stack_frame::current()) : exception {"The employee list does not exist."_t, frame} {
     }
     
-    employee_list_not_found_exception(const string& message, const stack_frame& sf = stack_frame::current()) : exception {message, sf} {
+    employee_list_not_found_exception(const string& message, const stack_frame& frame = stack_frame::current()) : exception {message, frame} {
     }
     
     template<typename exception_t>
-    employee_list_not_found_exception(const string& message, const exception_t& inner, const stack_frame& sf = stack_frame::current()) : exception {message, inner, sf} {
+    employee_list_not_found_exception(const string& message, const exception_t& inner, const stack_frame& frame = stack_frame::current()) : exception {message, inner, frame} {
     }
   };
 }