adds a cell check for the sample of the +roll gate
}
else {
u3_noun gim = u3k(u3h(a));
- u3_noun zor = u3k(u3r_at(u3x_sam_3, b));
- u3_noun daz = u3n_slam_on(u3k(b), u3nc(gim, zor));
+ u3_noun zor = u3r_at(u3x_sam, b);
+
+ if ( c3n == u3du(zor) ) {
+ return u3m_bail(c3__exit);
+ }
+
+ u3_noun daz = u3n_slam_on(u3k(b), u3nc(gim, u3k(u3t(zor))));
u3_noun vel = u3i_molt(u3k(b), u3x_sam_3, daz, 0);
if ( u3_none == vel ) {
