traceTo' work tracer ((HistoryRun tid cntr):rest) =
    do h <- tracer work tid cntr
       rest' <- traceTo' work tracer rest
       return $ h ++ rest'
traceTo' work tracer ((HistoryRun tid cntr):rest) =
    do h <- tracer work tid cntr
       rest' <- traceTo' work tracer rest
       return $ h ++ rest'
traceTo' work tracer ((HistoryRun tid cntr):rest) =
    do h <- tracer work tid cntr
       rest' <- traceTo' work tracer rest
       return $ h ++ rest'