1 files changed, 21 insertions, 0 deletions
diff --git a/src/Xanthous/Data.hs b/src/Xanthous/Data.hs
index e891a8e9e0d6..6e779a450525 100644
--- a/src/Xanthous/Data.hs
+++ b/src/Xanthous/Data.hs
@@ -17,6 +17,12 @@ module Xanthous.Data
   , loc
 
     -- *
+  , Dimensions'(..)
+  , Dimensions
+  , HasWidth(..)
+  , HasHeight(..)
+
+    -- *
   , Direction(..)
   , opposite
   , move
@@ -88,6 +94,21 @@ loc = iso hither yon
 
 --------------------------------------------------------------------------------
 
+data Dimensions' a = Dimensions
+  { _width :: a
+  , _height :: a
+  }
+  deriving stock (Show, Eq, Functor, Generic)
+  deriving anyclass (CoArbitrary, Function)
+makeFieldsNoPrefix ''Dimensions'
+
+instance Arbitrary a => Arbitrary (Dimensions' a) where
+  arbitrary = Dimensions <$> arbitrary <*> arbitrary
+
+type Dimensions = Dimensions' Word
+
+--------------------------------------------------------------------------------
+
 data Direction where
   Up        :: Direction
   Down      :: Direction