ghc-7.2.2: The GHC API




The Vectorisation monad.


The Vectorisation Monad

data VResult a Source

Vectorisation can either succeed with new envionment and a value, or return with failure.


Yes GlobalEnv LocalEnv a 

newtype VM a Source




runVM :: Builtins -> GlobalEnv -> LocalEnv -> DsM (VResult a)



liftDs :: DsM a -> VM aSource

Lift a desugaring computation into the vectorisation monad.

Error Handling

cantVectorise :: String -> SDoc -> aSource

Throw a pgmError saying we can't vectorise something.

maybeCantVectorise :: String -> SDoc -> Maybe a -> aSource

Like fromJust, but pgmError on Nothing.

maybeCantVectoriseM :: Monad m => String -> SDoc -> m (Maybe a) -> m aSource

Like maybeCantVectorise but in a Monad.


traceVt :: String -> SDoc -> VM ()Source

Output a trace message if -ddump-vt-trace is active.

dumpOptVt :: DynFlag -> String -> SDoc -> VM ()Source

Dump the given program conditionally.

dumpVt :: String -> SDoc -> VM ()Source

Dump the given program unconditionally.


noV :: VM aSource

Return some result saying we've failed.

traceNoV :: String -> SDoc -> VM aSource

Like traceNoV but also emit some trace message to stderr.

ensureV :: Bool -> VM ()Source

If True then carry on, otherwise fail.

traceEnsureV :: String -> SDoc -> Bool -> VM ()Source

Like ensureV but if we fail then emit some trace message to stderr.

onlyIfV :: Bool -> VM a -> VM aSource

If True then return the first argument, otherwise fail.

tryV :: VM a -> VM (Maybe a)Source

Try some vectorisation computaton. If it succeeds then return Just the result, otherwise return Nothing.

maybeV :: VM (Maybe a) -> VM aSource

If Just then return the value, otherwise fail.

traceMaybeV :: String -> SDoc -> VM (Maybe a) -> VM aSource

Like maybeV but emit a message to stderr if we fail.

orElseV :: VM a -> VM a -> VM aSource

Try the first computation, if it succeeds then take the returned value, if it fails then run the second computation instead.

fixV :: (a -> VM a) -> VM aSource

Fixpoint in the vectorisation monad.