9 :! $HC $HC_OPTS -no-recomp -c A.hs
16 -- swap A2 for A, compile & reload
18 :! $HC $HC_OPTS -no-recomp -c A.hs
20 -- the system should ignore the compiled version and compile its own.
26 -- pick up newly compiled A
33 -- remove A.o: system should recompile A