box type

lib/Quox/Parser/Parser.idr

@@ -203,8 +203,9 @@ mutual
     succCase : Grammar True (BName, PQty, BName, PTerm)
     succCase = do
       resC "succ"
-      n   <- bname
-      ih  <- option (Zero, Nothing) $ bracks [|MkPair qty (resC "." *> bname)|]
+      n  <- bname
+      ih <- option (Zero, Nothing) $
+        resC "," *> [|MkPair qty (resC "." *> bname)|]
       rhs <- darr *> term
       pure $ (n, fst ih, snd ih, rhs)
 
@@ -263,17 +264,20 @@ mutual
   private covering
   aTerm : Grammar True PTerm
   aTerm = [|Enum $ braces $ commaSep bareTag|]
+      <|> foldr1 Pair <$> parens (commaSep1 term)
+      <|> boxTerm
       <|> [|TYPE universe|]
       <|> Nat  <$ resC "ℕ"
       <|> Zero <$ resC "zero"
       <|> (nat <&> \n => fromNat n :# Nat)
       <|> [|V name|]
       <|> [|Tag tag|]
-      <|> foldr1 Pair <$> parens (commaSep1 term)
-  where
-    fromNat : Nat -> PTerm
-    fromNat 0     = Zero
-    fromNat (S k) = Succ $ fromNat k
+
+  private covering
+  boxTerm : Grammar True PTerm
+  boxTerm = bracks $
+        [|BOX (qty <* resC ".") term|]
+    <|> [|Box term|]
 
   private covering
   optBinderTerm : Grammar True (BName, PTerm)