Item 18: Make interfaces easy to use correctly and hard to use incorrectly(Effective C++)

Good interfaces are easy to use correctly and hard to use incorrectly. Your should strive for these characteristics in all your interfaces.

Ways to facilitate correct use include consistency in interfaces and behavioral compatibility with built-in types.

Ways to prevent errors include creating new types, restricting operations on types, constraining object values, and eliminating client resource management responsibilities.

TR1::shared_ptr supports custom deleters. This prevents the cross-DLL problem, can be used to automatically unlock mutexes (see Item 14), etc.

1 #include <iostream>
2 #include <string>
3 #include <boost/shared_ptr.hpp>
4 #include <fstream>
5 using namespace std;
6
7 class Test
8 {
9 public:
void test(Test* t)
{
ofstream out("1.txt");
out << "test in class" << endl;
out.close();
}
};

void test(Test* t)
{
ofstream out("1.txt");
out << "test in global" << endl;
out.close();
}

void a()
{
Test* t = new Test();
//void (Test::*funcPtr)(Test*) = &Test::test;
boost::shared_ptr<Test> sp(t, test);
}

int main()
{
a();

cin.get();
return 0;
}