| 81EFA |  {}N | ( obn..ob1 #n → {obn..ob1}) | 
| 81EF0 |  ::N | ( ob1..obn #n → :: ob1..obn ; ) | 
| 81F04 |  SYMBN | ( ob1..obn #n → sym) | 
| 8490C |  top&Cr | ( meta1 meta2 → symb )Does
 top&then <REF>SYMBN: . | 
| 81F0E |  EXTN | ( ob1..obn #n → u )Builds a unit object.
 | 
| 82E77 |  P::N | ( ob1..obn #n → seco )Build seco with possible garbage collection.
 |