c = d.next()
	if !utf16.IsSurrogate(r) || c != '\\' {
		d.scratch.addRune(r)
		goto scan
	}
	if c = d.next(); c != 'u' {
		d.scratch.addRune(r)
		goto scan_esc
	}

	r2 := d.u4()
	if r2 < 0 {
		return "", d.mkError(ErrSyntax, "in unicode escape sequence")
	}

	// write surrogate pair
	d.scratch.addRune(utf16.DecodeRune(r, r2))
	c = d.next()
	goto scan
}

pkg syscall (windows-amd64), const WSAENOPROTOOPT = 10042 #62254
pkg syscall (windows-amd64), const WSAENOPROTOOPT Errno #62254
pkg syscall, const EBADMSG Errno #67998
pkg syscall, const EPROTO Errno #67998
pkg unicode/utf16, func RuneLen(int32) int #44940
pkg unique, func Make[$0 comparable]($0) Handle[$0] #62483
pkg unique, method (Handle[$0]) Value() $0 #62483

 * string {@code "Foo<Bar>"}.
 *
 * <p><b>Note:</b> This class is similar to {@link CharEscaper} but with one very important
 * difference. A CharEscaper can only process Java <a
 * href="http://en.wikipedia.org/wiki/UTF-16">UTF16</a> characters in isolation and may not cope
 * when it encounters surrogate pairs. This class facilitates the correct escaping of all Unicode
 * characters.
 *