c++ - Is it guaranteed that size_t, vector::size_type, etc typedefs won't bind to a char type? -


it possible cstdint typedefs bind char variables. example, uint_least8_t binds unsigned char, , int_least8_t binds signed char.

does standard guarantee similar thing won't happen size_t or similar types? or there @ least purely theoretical chance such types bind char types, unsigned char or maybe wchar_t?

all know std::size_t is:

the type size_t implementation-defined unsigned integer type large enough contain size in bytes of object.

if unsigned char fulfills condition, may used std::size_t.

however, concern purely theoretical there not single real platform (that know of) unsigned char wide enough (alright, wrong) char type used std::size_t or like.

if super paranoid, can promote value @ least int unary +:

std::cout << +vector.size();

this print number if size type character type.

for reading can use variables of type std::common_type<unsigned int, std::size_t>::type (probably through typedef) , bounds check in case sizeof(int) > sizeof(std::size_t).


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