Merge pull request #38 from ethul/topic/dependency-graph

Topic/dependency graph

1 files changed, 49 insertions, 0 deletions

diff --git a/src/PursLoader/Plugin.purs b/src/PursLoader/Plugin.purs
new file mode 100644
index 0000000..23f8600
--- /dev/null
+++ b/src/PursLoader/Plugin.purs
@@ -0,0 +1,49 @@
+module PursLoader.Plugin
+  ( Result()
+  , Compile()
+  , Context()
+  , ImmutableMap()
+  , DependencyGraph()
+  , get
+  , dependenciesOf
+  ) where
+
+import Prelude (Unit())
+
+import Control.Monad.Eff (Eff())
+import Control.Monad.Eff.Exception (Error())
+
+import Data.Either (Either(..))
+import Data.Function (Fn4(), runFn4)
+import Data.Maybe (Maybe(..))
+import Data.Nullable (Nullable())
+
+type Result = { srcMap :: ImmutableMap String String, ffiMap :: ImmutableMap String String, graph :: DependencyGraph }
+
+type Compile eff = Nullable Error -> Result -> Eff eff Unit
+
+type Context eff = { compile :: Compile eff -> Eff eff Unit }
+
+get :: forall key value. ImmutableMap key value -> key -> Maybe value
+get = runFn4 getFn Nothing Just
+
+dependenciesOf :: DependencyGraph -> String -> Either Error (Array String)
+dependenciesOf = runFn4 dependenciesOfFn Left Right
+
+foreign import data ImmutableMap :: * -> * -> *
+
+foreign import data DependencyGraph :: *
+
+foreign import getFn
+  :: forall key value. Fn4 (Maybe value)
+                           (value -> Maybe value)
+                           (ImmutableMap key value)
+                           key
+                           (Maybe value)
+
+foreign import dependenciesOfFn
+  :: Fn4 (Error -> Either Error (Array String))
+         (Array String -> Either Error (Array String))
+         DependencyGraph
+         String
+         (Either Error (Array String))