diff --git a/src/Commands.newt b/src/Commands.newt
index 85d48de..006edf2 100644
--- a/src/Commands.newt
+++ b/src/Commands.newt
@@ -16,6 +16,7 @@ import Data.SortedMap
 import Lib.Parser
 import Lib.Syntax
 import Lib.Parser.Impl
+import Lib.Error
 
 -- For now we cheat and assume capitalized directories are a module component
 decomposeName : String → String × String
@@ -31,8 +32,12 @@ decomposeName fn =
 
 switchModule : FileSource → String → M (Maybe ModContext)
 switchModule repo modns = do
+    -- TODO processing on hover is expensive, but info is not always there
+    -- I suspect this picks up the case where a file has been invalidated by a change to
+    -- another file and we switch editors. Handle that (enqueue a check) and switch this back.
     top <- getTop
-    let (Just mod) = lookupMap' modns top.modules | Nothing => pure Nothing
+    mod <- processModule emptyFC repo Nil modns
+    -- let (Just mod) = lookupMap' modns top.modules | Nothing => pure Nothing
     modifyTop [ currentMod := mod; ops := mod.modOps ]
     pure $ Just mod
 
diff --git a/src/LSP.newt b/src/LSP.newt
index 5b46134..9520db8 100644
--- a/src/LSP.newt
+++ b/src/LSP.newt
@@ -15,6 +15,7 @@ import Node
 import Commands
 import Lib.ProcessDecl
 import Lib.Prettier
+import Lib.Error
 
 pfunc js_castArray : Array JSObject → JSObject := `x => x`
 pfunc js_castInt : Int → JSObject := `x => x`
diff --git a/src/Lib/Common.newt b/src/Lib/Common.newt
index 6940598..d5304e2 100644
--- a/src/Lib/Common.newt
+++ b/src/Lib/Common.newt
@@ -113,6 +113,8 @@ record FC where
   file : String
   bnds : Bounds
 
+instance Show FC where
+  show (MkFC file (MkBounds l c el ec)) = "\{file}:\{show $ l + 1}:\{show $ c + 1}--\{show $ el + 1}:\{show $ ec + 1}"
 
 instance Add FC where
   MkFC fn a + MkFC _ b = MkFC fn (a + b)
@@ -158,40 +160,6 @@ instance Show QName where
 instance Ord QName where
   compare (QN ns nm) (QN ns' nm') = if ns == ns' then compare nm nm' else compare ns ns'
 
--- I'll want to get Context / Val in some of these
--- and a pretty printer in the monad
-data Error
-  = E FC String
-  | ENotFound FC String
-  | Postpone FC QName String
-
-instance Show FC where
-  show (MkFC file (MkBounds l c el ec)) = "\{file}:\{show $ l + 1}:\{show $ c + 1}--\{show $ el + 1}:\{show $ ec + 1}"
-
-instance HasFC Error where
-  getFC (E x str) = x
-  getFC (ENotFound x _) = x
-  getFC (Postpone x k str) = x
-
-errorMsg : Error -> String
-errorMsg (E x str) = str
-errorMsg (ENotFound x nm) = "\{nm} not in scope"
-errorMsg (Postpone x k str) = str
-
-showError : (src : String) -> Error -> String
-showError src err =
-  let fc = getFC err
-  in "ERROR at \{show $ getFC err}: \{errorMsg err}\n" ++ go fc 0 (lines src)
-  where
-    go : FC → Int → List String → String
-    go fc l Nil = ""
-    go fc l (x :: xs) =
-      if l == fcLine fc then
-        let width = fc.bnds.endCol - fc.bnds.startCol in
-        "  \{x}\n  \{replicate (cast $ fcCol fc) ' '}\{replicate (cast width) '^'}\n"
-      else if fcLine fc - 3 < l then "  " ++ x ++ "\n" ++ go fc (l + 1) xs
-      else go fc (l + 1) xs
-
 data Fixity = InfixL | InfixR | Infix
 
 
diff --git a/src/Lib/Elab.newt b/src/Lib/Elab.newt
index 8e689d9..1327991 100644
--- a/src/Lib/Elab.newt
+++ b/src/Lib/Elab.newt
@@ -13,6 +13,7 @@ import Lib.Util
 import Lib.TopContext
 import Lib.Syntax
 import Lib.Types
+import Lib.Error
 
 vprint : Context -> Val -> M String
 vprint ctx v = do
diff --git a/src/Lib/Error.newt b/src/Lib/Error.newt
new file mode 100644
index 0000000..b8c91a2
--- /dev/null
+++ b/src/Lib/Error.newt
@@ -0,0 +1,37 @@
+module Lib.Error
+
+import Prelude
+import Lib.Common
+
+-- I'll want to get Context / Val in some of these
+-- and a pretty printer in the monad
+data Error
+  = E FC String
+  | ENotFound FC String
+  | Postpone FC QName String
+
+
+instance HasFC Error where
+  getFC (E x str) = x
+  getFC (ENotFound x _) = x
+  getFC (Postpone x k str) = x
+
+errorMsg : Error -> String
+errorMsg (E x str) = str
+errorMsg (ENotFound x nm) = "\{nm} not in scope"
+errorMsg (Postpone x k str) = str
+
+showError : (src : String) -> Error -> String
+showError src err =
+  let fc = getFC err
+  in "ERROR at \{show $ getFC err}: \{errorMsg err}\n" ++ go fc 0 (lines src)
+  where
+    go : FC → Int → List String → String
+    go fc l Nil = ""
+    go fc l (x :: xs) =
+      if l == fcLine fc then
+        let width = fc.bnds.endCol - fc.bnds.startCol in
+        "  \{x}\n  \{replicate (cast $ fcCol fc) ' '}\{replicate (cast width) '^'}\n"
+      else if fcLine fc - 3 < l then "  " ++ x ++ "\n" ++ go fc (l + 1) xs
+      else go fc (l + 1) xs
+
diff --git a/src/Lib/Parser/Impl.newt b/src/Lib/Parser/Impl.newt
index a58fbd9..0ebb516 100644
--- a/src/Lib/Parser/Impl.newt
+++ b/src/Lib/Parser/Impl.newt
@@ -7,7 +7,7 @@ import Data.String
 import Data.Int
 import Data.List1
 import Data.SortedMap
-
+import Lib.Error
 
 TokenList : U
 TokenList = List BTok
diff --git a/src/Lib/ProcessDecl.newt b/src/Lib/ProcessDecl.newt
index 6bb8605..179efc6 100644
--- a/src/Lib/ProcessDecl.newt
+++ b/src/Lib/ProcessDecl.newt
@@ -6,6 +6,7 @@ import Data.String
 
 import Lib.Common
 import Lib.Elab
+import Lib.Error
 import Lib.Parser
 import Lib.Syntax
 import Data.SortedMap
diff --git a/src/Lib/ProcessModule.newt b/src/Lib/ProcessModule.newt
index 9cb5463..4d0ecb9 100644
--- a/src/Lib/ProcessModule.newt
+++ b/src/Lib/ProcessModule.newt
@@ -4,6 +4,7 @@ import Prelude
 import Lib.Types
 import Lib.Common
 import Lib.Syntax
+import Lib.Error
 import Lib.ProcessDecl
 import Lib.TopContext
 import Lib.Tokenizer
diff --git a/src/Lib/Tokenizer.newt b/src/Lib/Tokenizer.newt
index 4c659f5..7109be9 100644
--- a/src/Lib/Tokenizer.newt
+++ b/src/Lib/Tokenizer.newt
@@ -12,6 +12,7 @@ import Lib.Token
 import Lib.Common
 import Data.String
 import Data.SnocList
+import Lib.Error
 
 standalone : List Char
 standalone = unpack "()\\{}[],.@;"
diff --git a/src/Lib/TopContext.newt b/src/Lib/TopContext.newt
index cb201f9..d48201e 100644
--- a/src/Lib/TopContext.newt
+++ b/src/Lib/TopContext.newt
@@ -6,6 +6,7 @@ import Data.String
 import Prelude
 import Lib.Common
 import Lib.Types
+import Lib.Error
 
 -- TODO move the def in here (along with M) or merge this into types
 -- The Monad can be its own file if we pull all of the monad update functions there.
diff --git a/src/Lib/Types.newt b/src/Lib/Types.newt
index dd427a4..0818801 100644
--- a/src/Lib/Types.newt
+++ b/src/Lib/Types.newt
@@ -3,6 +3,7 @@ module Lib.Types
 import Prelude
 import Lib.Common
 import Lib.Prettier
+import Lib.Error
 
 import Data.IORef
 import Data.SnocList
diff --git a/src/Main.newt b/src/Main.newt
index a7ecc02..d8a1a6c 100644
--- a/src/Main.newt
+++ b/src/Main.newt
@@ -19,6 +19,7 @@ import Lib.Syntax
 import Lib.ReplParser
 import Node
 import Revision
+import Lib.Error
 
 dirFileSource : String → FileSource
 dirFileSource base = MkFileSource base $ \fc fn => do