module Language.PureScript.ModuleDependencies (
sortModules,
ModuleGraph
) where
import Control.Monad.Error.Class (MonadError(..))
import Data.Graph
import Data.List (nub)
import Data.Maybe (fromMaybe)
import Language.PureScript.Crash
import Language.PureScript.AST
import Language.PureScript.Names
import Language.PureScript.Types
import Language.PureScript.Errors
type ModuleGraph = [(ModuleName, [ModuleName])]
sortModules :: (MonadError MultipleErrors m) => [Module] -> m ([Module], ModuleGraph)
sortModules ms = do
let verts = map (\m@(Module _ _ _ ds _) -> (m, getModuleName m, nub (concatMap usedModules ds))) ms
ms' <- mapM toModule $ stronglyConnComp verts
let (graph, fromVertex, toVertex) = graphFromEdges verts
moduleGraph = do (_, mn, _) <- verts
let v = fromMaybe (internalError "sortModules: vertex not found") (toVertex mn)
deps = reachable graph v
toKey i = case fromVertex i of (_, key, _) -> key
return (mn, filter (/= mn) (map toKey deps))
return (ms', moduleGraph)
usedModules :: Declaration -> [ModuleName]
usedModules d =
let (f, _, _, _, _) = everythingOnValues (++) forDecls forValues (const []) (const []) (const [])
(g, _, _, _, _) = accumTypes (everythingOnTypes (++) forTypes)
in nub (f d ++ g d)
where
forDecls :: Declaration -> [ModuleName]
forDecls (ImportDeclaration mn _ _ _) = [mn]
forDecls (FixityDeclaration _ _ (Just (Left (Qualified (Just mn) _)))) = [mn]
forDecls (FixityDeclaration _ _ (Just (Right (Qualified (Just mn) _)))) = [mn]
forDecls (TypeInstanceDeclaration _ _ (Qualified (Just mn) _) _ _) = [mn]
forDecls _ = []
forValues :: Expr -> [ModuleName]
forValues (Var (Qualified (Just mn) _)) = [mn]
forValues (Constructor (Qualified (Just mn) _)) = [mn]
forValues _ = []
forTypes :: Type -> [ModuleName]
forTypes (TypeConstructor (Qualified (Just mn) _)) = [mn]
forTypes _ = []
toModule :: (MonadError MultipleErrors m) => SCC Module -> m Module
toModule (AcyclicSCC m) = return m
toModule (CyclicSCC [m]) = return m
toModule (CyclicSCC ms) = throwError . errorMessage $ CycleInModules (map getModuleName ms)