-int str_hier_prefix(char *str, char *prefix, uns sep);
-int str_hier_suffix(char *str, char *suffix, uns sep); /** Like @str_hier_prefix(), but for suffixes. **/
+int str_hier_prefix(const char *str, const char *prefix, uns sep);
+int str_hier_suffix(const char *str, const char *suffix, uns sep); /** Like @str_hier_prefix(), but for suffixes. **/