I have two questions about using Hoopl:

1) I'm debugging some Hoopl transformations that often fall into an infinite 
loop. Probably the easiest way to find the cause would be to allow only a 
limited number of iterations and then examining the rewritten output. I think 
that optimization fuel was designed exactly with this scenario in mind, but 
Compiler.Hoopl module in hoopl library does not re-export functions needed to 
use Fuel (e.g. runWithFuel). Why are these functions hidden? Is there another 
interface for using fuel?

2) In my algorithm I need to initialize all of the blocks in a graph with 
bottom element of a lattice, except for the entry block, which needs some other 
initial values. I've written something like this:

cmmCopyPropagation dflags graph = do
    let entry_blk = g_entry graph
    g' <- dataflowPassFwd graph [(entry_blk, (Top , Top))] $
            analRewFwd cpLattice cpTransfer cpRewrite
    return . fst $ g'

cpLattice = DataflowLattice "copy propagation" (Bottom, Bottom) cpJoin

However, it seems that Bottom values passed to cpLattice are ignored - I could 
replace them with `undefined` and the code would still run without causing an 
error. Is there something obviously wrong in the way I pass initial fact values 
to dataflowPassFwd, or should I look for the problem in other parts of my code?

Janek

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