Is wchar_t needed for unicode support?

Question

Is the wchar_t type required for unicode support? If not then what\'s the point of this multibyte type? Why would you use wchar_t when you could accomplish the

Answer 1

As has already been noted, wchar_t is absolutely not necessary for unicode support. Not only that, it is also utterly useless for that purpose, since the standard provides no fixed-size guarantee for wchar_t (in other words, you don't know ahead of time what sizeof( wchar_t ) will be on a particular system), whereas sizeof( char ) will always be 1.

In a UTF-8 encoding, any actual UNICODE character is mapped to a sequence of one or more (up to four, I believe) octets. In a UTF-16 encoding, any actual UNICODE character is mapped to a sequence of one or more (up to two, I believe) 16-bit words. In a UTF-32 encoding, any actual UNICODE character is mapped to exactly one 32-bit-word.

As you can see, wchar_t could be of some use for implementing UTF-16 support IF the standard was nice enough to guarantee that wchar_t is always 16 bits wide. Unfortunately it does not, so you'd have to revert to a fixed-width integer type from (such as std::uint16_t) anyway.

What's more infuriating is the additional confusion caused by Microsoft's Visual Studio UNICODE and MBCS (multi-byte character set) build configurations. Both of these are

A) confusing and B) an outright lie

because neither does a "UNICODE" configuration in Visual Studio do anything to buy the programmer actual Unicode support, nor does the difference implied by these 2 build configurations make any sense. To explain, Microsoft recommends using TCHAR instead of using char or wchar_t directly. In an MBCS configuration, TCHAR expands to char, meaning you could potentially use this to implement UTF-8 support. In a UNICODE configuration, it expands to wchar_t, which in Visual Studio happens to be 16 bits wide and could potentially be used to implement UTF-16 support (which, as far as I'm aware, is the native encoding used by Windows). However, both of these encodings are multi-byte character sets, since both UTF-8 and UTF-16 allow for the possibility that a particular Unicode character may be encoded as more than a one char/wchar_t respectively, so the term multi-byte character set (as opposed to single-byte character set?) makes little sense.

To add insult to injury, merely using the Unicode configuration does not actually give you one iota of Unicode support. To actually get that, you have to use an actual Unicode library like ICU ( http://site.icu-project.org/ ). In short, the wchar_t type and Microsoft's MBCS and UNICODE configurations add nothing of any use and cause unnecessary confusion, and the world would be a significantly better place if none of them had ever been invented.