+extern const word *Uexpand_lig(uns x);
+
+enum unicode_char_type {
+ _U_LETTER = 1, /* Letters */
+ _U_UPPER = 2, /* Upper-case letters */
+ _U_LOWER = 4, /* Lower-case letters */
+ _U_CTRL = 8, /* Control characters */
+ _U_DIGIT = 16, /* Digits */
+ _U_XDIGIT = 32, /* Hexadecimal digits */
+ _U_SPACE = 64, /* White spaces (spaces, tabs, newlines) */
+ _U_LIGATURE = 128, /* Compatibility ligature (to be expanded) */
+};
+
+#define _U_LUPPER (_U_LETTER | _U_UPPER)
+#define _U_LLOWER (_U_LETTER | _U_LOWER)
+