module if2 {
             over 3 : read &c
             c=not (stackitem() and stackitem(2))
}
module ifelse1 {
             over 3 : read &c
             c=not (stackitem() and not stackitem(2))
}
module ifelse2 {
             over 3 : read &c
             c=not (stackitem(2) and not stackitem())
}
module ifelse {
             over 3 : read &c
             c=stackitem() or stackitem(2)
}
module endif2 {
             if not empty then drop 3
}
ctrl=true
for a=1 to 2
      for b=1 to 2
            Print "a=";a, "b=";b
            if2 a=1, b=2, &ctrl : Part {
                  print "both", a, b
            } as ctrl
            ifelse1 : Part {
                  print "first", a
            } as ctrl
            ifelse2  : Part {
                  print "second", b
            } as ctrl
            ifelse  : part {
                  print "no one"
            } as ctrl
            endif2
      next b
next a
Print "ok"