[plt-scheme] mzchar and wchar_t

At Tue, 14 Mar 2006 12:36:05 +0100, Jean-Guillaume wrote:
> Is there a simple relation between mzchar and wchar_t (and wint_t)  
> types ?

If you have a wchar_t whose value that is in [0, #xD7FF] or [#xE000,
#xFFFF], then you can use it as a mzchar and vice-versa.

More generally, a mzchar is a 4-byte value that is a Unicode scalar
value, and a wchar_t is a 2-byte value that is potentially a surrogate.
You can convert between strings of each type of character by UTF-16
decoding/decoding, perhaps using scheme_utf8_encode() and
scheme_utf8_decode() (which, despite the names, support a UTF-16 mode).
Beware of decoding a wchar_t string that may have unpaired surrogates.

Matthew