fix run command

data/scenarios/Tutorials/farming.yaml

@@ -36,7 +36,7 @@ objectives:
           n <- count "lambda";
           return (n >= 256)
         }
-      } { return false }
+      } {return false}
   - goal:
       - Congratulations!  You have completed the most difficult simulated exercise and are ready to begin exploring the new planet in earnest.  Of course there is much more remaining to explore in the world, and many additional programming language features to unlock.
       - |

env.txt

@@ -1 +1 @@
-Ctx {unCtx = fromList [("mp",Requirements {capReqs = fromList [CPower,CMove,CPlace], devReqs = fromList [], invReqs = fromList []}),("rr",Requirements {capReqs = fromList [CPower,CMove,CTurn,CPlace,CLambda], devReqs = fromList [], invReqs = fromList []}),("x4",Requirements {capReqs = fromList [CPower,CLambda], devReqs = fromList [], invReqs = fromList []})]}
+Ctx {unCtx = fromList []}

src/swarm-engine/Swarm/Game/CESK.hs

@@ -73,11 +73,13 @@ module Swarm.Game.CESK (
   continue,
   cancel,
   resetBlackholes,
+  prepareTerm,
 
   -- ** Extracting information
   finalValue,
   suspendedEnv,
   store,
+  cont,
 ) where
 
 import Control.Lens (Lens', Traversal', lens, traversal, (^.))
@@ -322,6 +324,23 @@ store = lens get set
     Waiting t c -> Waiting t (set c s)
     Suspended v e _ k -> Suspended v e s k
 
+-- | Lens focusing on the continuation of a CESK machine.
+cont :: Lens' CESK Cont
+cont = lens get set
+ where
+  get = \case
+    In _ _ _ k -> k
+    Out _ _ k -> k
+    Up _ _ k -> k
+    Waiting _ c -> get c
+    Suspended _ _ _ k -> k
+  set cesk k = case cesk of
+    In t e s _ -> In t e s k
+    Out v s _ -> Out v s k
+    Up x s _ -> Up x s k
+    Waiting t c -> Waiting t (set c k)
+    Suspended v e s _ -> Suspended v e s k
+
 -- | Create a brand new CESK machine, with empty environment and
 --   store, to evaluate a given term.  We always initialize the
 --   machine with a single FExec frame as the continuation; if the
@@ -331,14 +350,14 @@ initMachine t = In (prepareTerm mempty t) mempty emptyStore [FExec]
 
 -- | Load a program into an existing robot CESK machine: either
 --   continue from a suspended state, or, as a fallback, start from
---   scratch with an empty environment.
+--   scratch with an empty environment but the same store.
 --
 --   Also insert a @suspend@ primitive at the end, so the resulting
 --   term is suitable for execution by the base (REPL) robot.
 continue :: TSyntax -> CESK -> CESK
 continue t = \case
   Suspended _ e s k -> In (insertSuspend $ prepareTerm e t) e s (FExec : k)
-  _ -> In (insertSuspend $ prepareTerm mempty t) mempty emptyStore [FExec]
+  cesk -> In (insertSuspend $ prepareTerm mempty t) mempty (cesk ^. store) [FExec]
 
 -- | Prepare a term for evaluation by a CESK machine in the given
 --   environment: erase all type annotations, and optionally wrap it

src/swarm-engine/Swarm/Game/Step/Const.hs

@@ -87,6 +87,7 @@ import Swarm.Game.Tick
 import Swarm.Game.Universe
 import Swarm.Game.Value
 import Swarm.Language.Capability
+import Swarm.Language.Elaborate (insertSuspend)
 import Swarm.Language.Key (parseKeyComboFull)
 import Swarm.Language.Pipeline
 import Swarm.Language.Pretty (prettyText)
@@ -1227,8 +1228,11 @@ execConst runChildProg c vs s k = do
           Nothing -> return $ mkReturn ()
           Just pt -> do
             void $ traceLog CmdStatus Info "run: OK."
-            cesk <- use machine
-            return $ continue pt cesk
+            case k of
+              [] -> return $ In (insertSuspend (prepareTerm mempty pt)) mempty s [FExec]
+              _ -> return $ In (prepareTerm mempty pt) mempty s (FExec : k)
+      -- mempty above means we will wipe out all our current definitions every time
+      -- we execute 'run'...
       _ -> badConst
     Not -> case vs of
       [VBool b] -> return $ Out (VBool (not b)) s k