notes on typeclass

src/Lib/Check.idr

@@ -102,6 +102,9 @@ parameters (ctx: Context)
 
   solve : Nat -> Nat -> SnocList Val -> Val  -> M  ()
   solve l m sp t = do
+    debug "solve \{show l} \{show m} \{show sp} \{show t}"
+    meta <- lookupMeta m
+    debug "meta \{show meta}"
     ren <- invert l sp
     tm <- rename m ren l t
     let tm = lams (length sp) tm
@@ -156,6 +159,7 @@ parameters (ctx: Context)
       (VLam fc _ t,  t'       ) => unify (l + 1) !(t $$ VVar emptyFC l [<]) !(t' `vapp` VVar emptyFC l [<])
       (VMeta fc k sp,  VMeta fc' k' sp' ) =>
         if k == k' then unifySpine l (k == k') sp sp'
+        -- TODO, might want to try the other way, too.
         else solve l k sp (VMeta fc' k' sp') >> pure neutral
       (t,           VMeta fc' i' sp') => solve l i' sp' t >> pure neutral
       (VMeta fc i sp, t'           ) => solve l i sp t' >> pure neutral

src/Lib/TT.idr

@@ -37,7 +37,7 @@ export
 freshMeta : Context -> FC -> Val -> M Tm
 freshMeta ctx fc ty = do
   mc <- readIORef ctx.metas
-  putStrLn "INFO at \{show fc}: fresh meta \{show mc.next}"
+  putStrLn "INFO at \{show fc}: fresh meta \{show mc.next} : \{show ty}"
   writeIORef ctx.metas $ { next $= S, metas $= (Unsolved fc mc.next ctx ty ::) } mc
   pure $ applyBDs 0 (Meta emptyFC mc.next) ctx.bds
   where

src/Lib/Types.idr

@@ -292,11 +292,6 @@ record Context
 public export
 data MetaEntry = Unsolved FC Nat Context Val | Solved Nat Val
 
-export
-covering
-Show MetaEntry where
-  show (Unsolved pos k xs ty) = "Unsolved \{show pos} \{show k} : \{show ty}"
-  show (Solved k x) = "Solved \{show k} \{show x}"
 
 public export
 record MetaContext where
@@ -366,6 +361,12 @@ record Context where
   metas : IORef MetaContext
   fc : FC
 
+export
+covering
+Show MetaEntry where
+  show (Unsolved pos k ctx ty) = "Unsolved \{show pos} \{show k} : \{show ty} \{show ctx.bds}"
+  show (Solved k x) = "Solved \{show k} \{show x}"
+
 export withPos : Context -> FC -> Context
 withPos ctx fc = { fc := fc } ctx