ghc-7.0.4: The GHC API

Vectorise.Monad.Base

Contents

Description

The Vectorisation monad.

Synopsis

The Vectorisation Monad

data VResult a

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

Constructors

Yes GlobalEnv LocalEnv a 
No 

newtype VM a

Constructors

VM 

Fields

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

Instances

Lifting

liftDs :: DsM a -> VM a

Lift a desugaring computation into the vectorisation monad.

Error Handling

cantVectorise :: String -> SDoc -> a

Throw a pgmError saying we can't vectorise something.

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

Like fromJust, but pgmError on Nothing.

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

Like maybeCantVectorise but in a Monad.

Control

noV :: VM a

Return some result saying we've failed.

traceNoV :: String -> SDoc -> VM a

Like traceNoV but also emit some trace message to stderr.

ensureV :: Bool -> VM ()

If True then carry on, otherwise fail.

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

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

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

If True then return the first argument, otherwise fail.

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

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

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

If Just then return the value, otherwise fail.

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

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

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

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 a

Fixpoint in the vectorisation monad.