Ap |bool |is_uni_xdigit_lc|UV c
Apd |STRLEN |is_utf8_char |U8 *p
Apd |bool |is_utf8_string |U8 *s|STRLEN len
+Apd |bool |is_utf8_string_loc|U8 *s|STRLEN len|U8 **p
Ap |bool |is_utf8_alnum |U8 *p
Ap |bool |is_utf8_alnumc |U8 *p
Ap |bool |is_utf8_idfirst|U8 *p