1 files changed, 36 insertions, 0 deletions

diff --git a/events/src/Events/Spec.hs b/events/src/Events/Spec.hs
new file mode 100644
index 0000000..deabcc3
--- /dev/null
+++ b/events/src/Events/Spec.hs
@@ -0,0 +1,36 @@
+module Events.Spec
+       ( interpret
+       , Spec, Expr(..), BoolExpr(..)
+       ) where
+
+import Events.Types
+
+import Control.Monad.IO.Class
+import Control.Monad.State.Lazy
+
+import Data.Monoid
+import Data.Foldable
+import Control.Lens
+
+import Debug.Trace
+
+type Spec = [Expr] -- most significant last
+
+data Expr = Override Object
+          | Occurs BoolExpr
+          | Nop
+          deriving (Show)
+
+data BoolExpr = BoolLit Bool
+              deriving (Show)
+
+interpret :: MonadIO m => Spec -> Eval m ()
+interpret = mapM_ interpretExpr
+
+interpretExpr :: MonadIO m => Expr -> Eval m ()
+interpretExpr (Override obj) = ctxEvent ?= obj
+interpretExpr (Occurs expr)  = ctxOccurs <~ interpretBoolExpr expr
+interpretExpr _              = return ()
+
+interpretBoolExpr :: Monad m => BoolExpr -> Eval m Bool
+interpretBoolExpr (BoolLit v) = return v