true
andfalse
:true
is expressed by1
,ON
,YES
,TRUE
,Y
, or a non-zero number.false
is expressed by0
,OFF
,NO
,FALSE
,N
,IGNORE
,NOTFOUND
, the empty string, or ends in the suffix-NOTFOUND
.- while
if
,else
can be lower-case, butOR
should be upper-case.