goodbay java, hello c++ (again)

lambda_test.sh

echo '
#include <iostream>
#include <string>

using namespace std;

int main() {
   string x = "Hello";
   auto say_hi = [x] (string y) { return x + " lambda " + y; }; 
   cout << say_hi("world") << endl;
}
' | gcc -std=c++11 -xc++ - -lstdc++ -o app