TEST4 TESTS THE %%IF COMMAND BY OUTPUTTING THE LOGICAL VALUE OF X.
%IF X 0 <>
X is non-zero
%EIF
%IF X 0 =
X is zero (ERROR!).
%EIF
%IF X 25 < X 25 > !
X is not 25 (ERROR!).
%EIF
%IF NOTX 
NOTX is TRUE (non-zero)
%EIF
%IF NOTX NOT
NOTX is FALSE (zero)
%EIF
%IF REPLY1 
REPLY1 was "YES" ,"TRUE", or non-zero
%EIF
%IF REPLY1 NOT
REPLY1 was "NO", "FALSE", or non-zero (ERROR!).
%EIF
%if REPLY2 
REPLY2 was "YES", "TRUE", or zero (ERROR!)
%EIF
%IF REPLY2 NOT
REPLY2 was "NO", "FALSE", or zero.
%EIF
END OF TEST4