On 15 Aug 2011, at 07:57, Yakov Galka wrote:
It's not just for saving typing, it's for making the interface more generic. Consider the following:
void f(const char*); void f(const std::string&);
I can use it for null-terminated strings and for std::srings just fine. But consider the case I want to pass it a sub-string of some string, or a string stored in std::vector, or a non-null terminated string:
std::string str1 = ...; std::vector<char> str2 = ...; char str3[1024]; GetBinaryPacket(str3);
f(str1.substr(1, 5)); // unnecessary copy f(std::string(str2.begin(), str2.end())); // unnecessary copy f(std::string(str3, str3 + 5)); // unnecessary copy
Compare it with:
typedef iterator_range<const char*> str_ref; void f(str_ref);
f(str_ref(str1.data()+1, str1.data()+6)); // no copy f(str_ref(&str2[0], &str2[0] + str2.size())); // no copy f(str_ref(str3, str3 + 5)); // no copy
Is worrying about high efficiency, and lack of copying, in program_options really that important? I would prefer the simplest possible interface, even if it has some small inefficiencies. Chris