c++ - Unsigned string construction impossible -


i looking way string of unsigned chars. stumbled upon strings of unsigned chars

so answer create new typedef follows : 

typedef std::basic_string<unsigned char> ustring;

the thing is, i'm not able construct this. when try : 

char *p = "123123"; auto s = ustring(p);

i following error : 

no instance of constructor "std::basic_string<_elem, _traits,  _alloc>::basic_string [with _elem=unsigned char,  _traits=std::char_traits<unsigned char>, _alloc=std::allocator<unsigned  char>]" matches argument list

can please shed light on issue?

thanks in advance!

irrespective of whether or not char signed or unsigned on platform, char, unsigned char, , signed char all distinct types. rather int , long distinct types if have same number of bits , complement scheme.

so you'd have better luck with

const unsigned char* p = (const unsigned char*)"123123";

where i've inserted const qualification emphasise read-only nature of const char[7] literal.


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