Setting local variables from mapping sections does seem to work...

src/lib/server/map.c

@@ -527,7 +527,7 @@ ssize_t map_afrom_substr(TALLOC_CTX *ctx, map_t **out, map_t **parent_p, fr_sbuf
 		fr_strerror_const("Invalid operator");
 		goto error_adj;
 	}
-	
+
 	/*
 	 *	Validate operators for check items.
 	 *
@@ -967,12 +967,6 @@ static int _map_afrom_cs(TALLOC_CTX *ctx, map_list_t *out, map_t *parent, CONF_S
 			goto error;
 		}
 
-		if (tmpl_is_attr(map->lhs) && tmpl_attr_tail_da(map->lhs)->flags.local) {
-			cf_log_err(ci, "Invalid location for local attribute '%s'", map->lhs->name);
-			talloc_free(map);
-			goto error; /* re-do "goto marker" stuff to print out spaces ? */
-		}
-
 		MAP_VERIFY(map);
 
 		/*

src/tests/keywords/map

@@ -1,6 +1,14 @@
+string CSV-Result
+
 #
 #  PRE: map-2arg-error map-empty-error map-module-error map-field-error
 #
 map csv &User-Name {
-	&reply.Result-Status := field3
+	&CSV-Result := field3
 }
+
+if (!(&CSV-Result == "success")) {
+	test_fail
+}
+
+success