IFFALSE instructionlist
IFF instructionlist

Runs instructionlist if the most recent TEST instruction had a FALSE input. Does nothing, otherwise. The TEST must have been in the same procedure or a superprocedure.

TO MYTEST :arg
  TEST 1 = :arg
  PRINT [Do this]
  PRINT [Do that]
  IFTRUE [PRINT [arg was the number one]]
  IFFALSE [PRINT [arg was NOT the number one]]
END

MYTEST 0
Do this
Do that
arg was NOT the number one