:art: Make Sift abstract and final

diff --git a/src/lib/sift.c b/src/lib/sift.c
index 5a8c5e91fe6e106aabceeae21c9aff868a9e8bd3..8ecc99c64bb2b03a1cb877963ee7aeab512b2476 100644 (file)
--- a/src/lib/sift.c
+++ b/src/lib/sift.c
@@ -70,7 +70,8 @@ static OP_CHECK(opck_ctrl) {
 }
 
 GWION_IMPORT(sift) {
-  GWI_BB(gwi_class_ini(gwi, "Sift", "Shred"));
+  const Type sift = gwi_class_ini(gwi, "Sift", "Shred");
+  SET_FLAG(sift, abstract | ae_flag_final);
   GWI_BB(gwi_class_end(gwi));
 
   gwidoc(gwi, "This operator expands too\n"