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#include <string>
#include <iostream>
// Minimal class path
class path
{
public:
path(const char*)
{
std::cout << "path( const char * )\n";
}
path(const std::string&)
{
std::cout << "path( std::string & )\n";
}
// for maximum efficiency, either signature must work
#ifdef BY_VALUE
operator const std::string() const
#else
operator const std::string&() const
#endif
{
std::cout << "operator string\n";
return m_path;
}
#ifdef NAMED_CONVERSION
std::string string() const
{
std::cout << "std::string string() const\n";
return m_path;
}
#endif
private:
std::string m_path;
};
bool operator==(const path&, const path&)
{
std::cout << "operator==( const path &, const path & )\n";
return true;
}
// These are the critical use cases. If any of these don't compile, usability
// is unacceptably degraded.
void f(const path&)
{
std::cout << "f( const path & )\n";
}
int main()
{
f("foo");
f(std::string("foo"));
f(path("foo"));
std::cout << '\n';
std::string s1(path("foo"));
std::string s2 = path("foo");
s2 = path("foo");
#ifdef NAMED_CONVERSION
s2 = path("foo").string();
#endif
std::cout << '\n';
// these must call bool path( const path &, const path & );
path("foo") == path("foo");
path("foo") == "foo";
path("foo") == std::string("foo");
"foo" == path("foo");
std::string("foo") == path("foo");
return 0;
}
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