2 files changed, 59 insertions, 1 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
diff --git a/events/src/Main.hs b/events/src/Main.hs
index 1c56140..7f65b19 100644
--- a/events/src/Main.hs
+++ b/events/src/Main.hs
@@ -1,4 +1,26 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE OverloadedLists #-}
+
 import Events.Types
+import Events.Spec
+
+import qualified Data.Yaml as Yaml
+import qualified Data.ByteString.Char8 as CBS
+
+import Control.Lens
+import Control.Monad
+import Control.Monad.Trans
+import Data.Aeson.Lens
+import Data.Aeson
+
+import Debug.Trace
+
+import qualified ListT
 
 main :: IO ()
-main = undefined
+main = test $ [ -- Nop
+              -- , Override [("blub", String "Haha!")]
+              --,  Occurs (BoolLit True)
+              ]
+  where
+    test = CBS.putStr . Yaml.encode <=< evaluate . interpret