|string||A string or expression that evaluates to a string.|
$WISWIDE returns a boolean value indicating whether string contains surrogate pairs. 0=string does not contain any surrogate pairs. 1=string contains one or more surrogate pairs.
A surrogate pair is a pair of 16-bit InterSystems IRIS character elements that together encode a single Unicode character. Surrogate pairs are used to represent certain ideographs which are used in Chinese, Japanese kanji, and Korean hanja. (Most commonly-used Chinese, kanji, and hanja characters are represented by standard 16-bit Unicode encodings.) Surrogate pairs provide InterSystems IRIS support for the Japanese JIS X0213:2004 (JIS2004) encoding standard and the Chinese GB18030 encoding standard.
A surrogate pair consists of high-order 16-bit character element in the hexadecimal range D800 through DBFF, and a low-order 16-bit character element in the hexadecimal range DC00 through DFFF.
The following example shows $WISWIDE returning a boolean for a surrogate pair:
SET spair=$CHAR($ZHEX("D806"),$ZHEX("DC06")) /* surrogate pair */ SET xpair=$CHAR($ZHEX("DC06"),$ZHEX("D806")) /* NOT a surrogate pair */ SET str="AB"_spair_"CD" WRITE !,$WISWIDE(str)," = surrogate pair(s) in string?" SET xstr="AB"_xpair_"CD" WRITE !,$WISWIDE(xstr)," = surrogate pair(s) in string?"