-_Bool graph_matches_ident (graph_config_t *cfg, const graph_ident_t *ident);
-
-/* Compares the given string with the appropriate field of the selector. If the
- * selector field is "/all/" or "/any/", returns true without checking the
- * instances. See "graph_inst_search_field" for finding all matching instances.
- * */
+/* Returns true if the given "ident" matches the (more general) selector of
+ * the graph "cfg". */
+_Bool graph_ident_matches (graph_config_t *cfg, const graph_ident_t *ident);
+
+/* Returns true if the selector of the graph "cfg" matches the more general
+ * ident "selector". */
+_Bool graph_matches_ident (graph_config_t *cfg,
+ const graph_ident_t *selector);
+
+/* Returns true if a file may apply to both, the graphs selector and the
+ * selector given as argument. If the selectors contradict one another,
+ * returns false. */
+_Bool graph_ident_intersect (graph_config_t *cfg,
+ const graph_ident_t *selector);
+
+/* Compares the given string with the appropriate field of the selector. If
+ * the selector field is "/all/" or "/any/", returns true without checking the
+ * instances. See "graph_inst_search_field" for finding all matching
+ * instances. */