Converting the Ghc monad to the IO monad.

Initialize the DynFlags relating to the compilation of a single file or GHC session according to the Cradle and Options provided.

Printing necessary information for front-end booting.

Getting functions, classes, etc from a module. If detailed is True, their types are also obtained. If operators is True, operators are also returned.

Checking syntax of a target file using GHC. Warnings and errors are returned.

Obtaining information of a target expression. (GHCi's info:)

Obtaining type of a target expression. (GHCi's type:)

Listing installed modules.

Type of key for SymMdlDb.

Database from Symbol to modules.

Creating SymMdlDb.

Looking up SymMdlDb with Symbol to find modules.

Obtaining the directory for system libraries.

Lift a computation from the IO monad. This allows us to run IO computations in any monadic stack, so long as it supports these kinds of operations (i.e. IO is the base monad for the stack).

Example

import Control.Monad.Trans.State -- from the "transformers" library

printState :: Show s => StateT s IO ()
printState = do
  state <- get
  liftIO $ print state

• Couldn't match type ‘IO’ with ‘StateT s IO’
 Expected type: StateT s IO ()
   Actual type: IO ()

> evalStateT printState "hello"
"hello"

> evalStateT printState 3
3

Run function for the Ghc monad.

It initialises the GHC session and warnings via initGhcMonad. Each call to this function will create a new session which should not be shared among several threads.

Any errors not handled inside the Ghc action are propagated as IO exceptions.

A minimal implementation of a GhcMonad. If you need a custom monad, e.g., to maintain additional state consider wrapping this monad or using GhcT.