BloombergLP::bdlde::Utf8Util::advanceIfValid

Advance past 0 or more consecutive valid Unicode code points at the beginning of the specified string, until either the specified numCodePoints bytes or the whole string have been traversed, or invalid UTF‐8 is encountered (whichever occurs first), and return the number of Unicode code points traversed. Set the specified *status to 0 if no invalid UTF‐8 is encountered, and to a value from the ErrorStatus enum otherwise. Set the specified *result to the address of the byte immediately following the last valid code point traversed, or to string if its length or numCodePoints is 0. string need not be null‐terminated and can contain embedded null bytes. The behavior is undefined unless 0 <= numCodePoints. Note that the value returned will be in the range [0 .. numCodePoints]. Also note that string may contain less than string.length() Unicode code points.