-/* Copy, shrink, extend. */
-void ds_replace (struct string *, const char *);
+/* Replacement. */
+void ds_assign_string (struct string *, const struct string *);
+void ds_assign_substring (struct string *,
+ const struct string *, size_t start, size_t cnt);
+void ds_assign_buffer (struct string *, const char *, size_t);
+void ds_assign_c_str (struct string *, const char *);
+
+/* Shrink, extend. */