tock-mirror/common/Pass.hs
Neil Brown c97d1d00c8 Changed the error type from String to ErrorReport throughout the code
ErrorReport is of type (Maybe Meta, String), thereby adding an optional code position to error messages.

Die has been changed so that die and dieP are now implemented in terms of dieReport (:: ErrorReport -> m a).  This involved changing less code than changing die to be of type ErrorReport -> m a.  All that had to be changed directly was that Die instances now implement dieReport instead of die.

Any bits of code that "caught" errors has been changed so that it handles ErrorReport instead of String.  This ErrorReport is eventually, in Main, passed to dieIO, which will soon be changed to read the file in and provide the context.  Accordingly, MonadIO m has been added as a constraint to dieIO, and dieInternal has been changed to no longer use dieIO (because really we can't add the MonadIO constraint to dieInternal).

Various error messages have been changed.  Notably, all instances of fail in ParseOccam have been changed to use die or, wherever possible, dieP.  A similar thing has been done in EvalConstants and EvalLiterals.
2007-09-18 10:17:38 +00:00

114 lines
3.4 KiB
Haskell

{-
Tock: a compiler for parallel languages
Copyright (C) 2007 University of Kent
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 2 of the License, or (at your
option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program. If not, see <http://www.gnu.org/licenses/>.
-}
-- | Common definitions for passes over the AST.
module Pass where
import Control.Monad.Error
import Control.Monad.State
import Data.Generics
import Data.List
import System.IO
import qualified AST as A
import CompState
import Errors
import Metadata
import PrettyShow
import TreeUtil
-- | The monad in which AST-mangling passes operate.
type PassM = ErrorT ErrorReport (StateT CompState IO)
instance Die PassM where
dieReport = throwError
-- | The type of an AST-mangling pass.
type Pass = A.Process -> PassM A.Process
-- | Compose a list of passes into a single pass.
runPasses :: [(String, Pass)] -> A.Process -> PassM A.Process
runPasses [] ast = return ast
runPasses ((s, p):ps) ast
= do debug $ "{{{ " ++ s
progress $ "- " ++ s
ast' <- p ast
debugAST ast'
debug $ "}}}"
runPasses ps ast'
-- | Print a message if above the given verbosity level.
verboseMessage :: (CSM m, MonadIO m) => Int -> String -> m ()
verboseMessage n s
= do ps <- get
when (csVerboseLevel ps >= n) $
liftIO $ hPutStrLn stderr s
-- | Print a warning message.
warn :: (CSM m, MonadIO m) => String -> m ()
warn = verboseMessage 0
-- | Print out any warnings stored.
showWarnings :: (CSM m, MonadIO m) => m ()
showWarnings
= do ps <- get
sequence_ $ map warn (reverse $ csWarnings ps)
put $ ps { csWarnings = [] }
-- | Print a progress message.
progress :: (CSM m, MonadIO m) => String -> m ()
progress = verboseMessage 1
-- | Print a debugging message.
debug :: (CSM m, MonadIO m) => String -> m ()
debug = verboseMessage 2
-- | Print a really verbose debugging message.
veryDebug :: (CSM m, MonadIO m) => String -> m ()
veryDebug = verboseMessage 3
-- | Dump the AST and parse state.
debugAST :: (CSM m, MonadIO m) => A.Process -> m ()
debugAST p
= do veryDebug $ "{{{ AST"
veryDebug $ pshow p
veryDebug $ "}}}"
veryDebug $ "{{{ State"
ps <- get
veryDebug $ pshow ps
veryDebug $ "}}}"
-- | Number lines in a piece of text.
numberLines :: String -> String
numberLines s
= concat $ intersperse "\n" $ [show n ++ ": " ++ s
| (n, s) <- zip [1..] (lines s)]
-- | Make a generic rule for a pass.
makeGeneric :: (Data t) => (forall s. Data s => s -> PassM s) -> t -> PassM t
makeGeneric top
= (gmapM top)
`extM` (return :: String -> PassM String)
`extM` (return :: Meta -> PassM Meta)
excludeConstr :: Data a => [Constr] -> a -> PassM a
excludeConstr cons x
= if null items then return x else dieInternal (Nothing, "Excluded item still remains in source tree: " ++ (show $ head items) ++ " tree is: " ++ pshow x)
where
items = checkTreeForConstr cons x