old_mile.cpp and adl.cpp

cpp/adl.cpp

@@ -0,0 +1,59 @@
+/*
+VIM: let b:cf5build="clang -std=c++20 -O2 -pthread -lstdc++ -I. {SRC} -o {OUT}"
+VIM: let b:cf5run="{OUT}"
+VIM-: let b:cppflags=g:Iboost.g:Itbb
+VIM-: let b:ldflags=g:Lboost.g:Ltbb
+VIM-: let b:ldlibpath=g:Bboost.g:Btbb
+*/
+#include <iostream>
+#include <exception>
+#include <chrono>
+
+namespace ttt {
+ struct s {
+ };
+ void print( const s& t ){
+     std::cout << "ttt::print" << std::endl;
+ }
+}
+
+namespace C
+{
+    template <typename T>
+    void print( T t ){
+        std::cout << "C::print" << std::endl;
+    }
+
+    template <typename T>
+    void call_print( const T& t ){
+        print( t );
+    }
+};
+
+
+int main ( void )
+{try{
+    auto begin = std::chrono::high_resolution_clock::now();
+
+
+    //......
+    C::call_print(ttt::s{});
+
+    auto end = std::chrono::high_resolution_clock::now();
+    std::chrono::duration<double> seconds = end - begin;
+    std::cout << "Time: " << seconds.count() << std::endl;
+    return 0;
+}
+catch ( const std::exception& e )
+{
+    std::cerr << std::endl
+            << "std::exception(\"" << e.what() << "\")." << std::endl;
+    return 2;
+}
+catch ( ... )
+{
+    std::cerr  << std::endl
+            << "unknown exception." << std::endl;
+    return 1;
+}}
+