Model virtual machine ADT

MVM.cabal

@@ -24,7 +24,8 @@ executable MVM
     main-is:          Main.hs
 
     -- Modules included in this executable, other than Main.
-    -- other-modules:
+    other-modules:
+      VirtualMachine
 
     -- LANGUAGE extensions used by modules in this package.
     -- other-extensions:

app/VirtualMachine.hs

@@ -0,0 +1,20 @@
+module VirtualMachine (
+  VM(..),
+  empty
+)
+where
+
+import qualified Data.Sequence as S
+
+data VM = VM { pc :: Int
+             , fp :: Int
+             , stack :: S.Seq Int
+             , halt :: Bool
+             } deriving (Show, Eq)
+
+empty :: VM
+empty = VM { pc     = -1
+           , fp     = -1
+           , stack  = S.empty
+           , halt   = False
+           }