Add a close command

Add a close command, to close doors, that works basically the same as
the open command.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/Xanthous/Entities/Environment.hs b/src/Xanthous/Entities/Environment.hs
index 993714c844..430ce1b7a9 100644
--- a/src/Xanthous/Entities/Environment.hs
+++ b/src/Xanthous/Entities/Environment.hs
@@ -7,6 +7,7 @@ module Xanthous.Entities.Environment
     -- * Doors
   , Door(..)
   , open
+  , closed
   , locked
   , unlockedDoor
 
@@ -99,6 +100,9 @@ instance Entity Door where
   entityCollision door | door ^. open = Nothing
                        | otherwise = Just Stop
 
+closed :: Lens' Door Bool
+closed = open . involuted not
+
 -- | A closed, unlocked door
 unlockedDoor :: Door
 unlockedDoor = Door