ghc-7.6.1.20120913: The GHC API

Safe HaskellNone

DynamicLoading

Contents

Description

Dynamically lookup up values from modules and loading them.

Synopsis

Force loading information

forceLoadModuleInterfaces :: HscEnv -> SDoc -> [Module] -> IO ()Source

Force the interfaces for the given modules to be loaded. The SDoc parameter is used for debugging (-ddump-if-trace) only: it is shown as the reason why the module is being loaded.

forceLoadNameModuleInterface :: HscEnv -> SDoc -> Name -> IO ()Source

Force the interface for the module containing the name to be loaded. The SDoc parameter is used for debugging (-ddump-if-trace) only: it is shown as the reason why the module is being loaded.

forceLoadTyCon :: HscEnv -> Name -> IO TyConSource

Load the TyCon associated with the given name, come hell or high water. Fails if:

  • The interface could not be loaded * The name is not that of a TyCon * The name did not exist in the loaded module

Finding names

lookupRdrNameInModule :: HscEnv -> ModuleName -> RdrName -> IO (Maybe Name)Source

Finds the Name corresponding to the given RdrName in the context of the ModuleName. Returns Nothing if no such Name could be found. Any other condition results in an exception:

  • If the module could not be found * If we could not determine the imports of the module

Loading values

getValueSafely :: HscEnv -> Name -> Type -> IO (Maybe a)Source

Loads the value corresponding to a Name if that value has the given Type. This only provides limited safety in that it is up to the user to ensure that that type corresponds to the type you try to use the return value at!

If the value found was not of the correct type, returns Nothing. Any other condition results in an exception:

  • If we could not load the names module * If the thing being loaded is not a value * If the Name does not exist in the module * If the link failed

lessUnsafeCoerce :: DynFlags -> String -> a -> IO bSource

Coerce a value as usual, but:

1) Evaluate it immediately to get a segfault early if the coercion was wrong

2) Wrap it in some debug messages at verbosity 3 or higher so we can see what happened if it does segfault