working. checkpoint before messing with parser

src/Lib/Check.idr

@@ -6,10 +6,11 @@ import Lib.Parser.Impl
 import Data.Vect
 import Data.String
 import Lib.TT
+import Lib.TopContext
 import Syntax
 
 -- cribbed this, it avoids MonadError String m => everywhere
-parameters {0 m : Type -> Type} {auto _ : MonadError String m}
+parameters {0 m : Type -> Type} {auto _ : MonadError String m} (top : TopContext)
   export
   infer : Context -> Raw -> m (Tm, Val)
 
@@ -33,7 +34,7 @@ parameters {0 m : Type -> Type} {auto _ : MonadError String m}
 
   infer ctx (RVar nm) = go 0 ctx.types
     where
-      go : Nat -> List (String, Val) -> m (Tm, Val)
+      go : Nat -> Vect n (String, Val) -> m (Tm, Val)
       go i [] = throwError "\{show nm} not in scope \{show $ map fst ctx.types}"
       go i ((x, ty) :: xs) = if x == nm then pure $ (Bnd i, ty) 
         else go (i + 1) xs

src/Lib/Parser.idr

@@ -26,6 +26,11 @@ import Data.List
 -- exercises.  There is some fill in the parser stuff that may show 
 -- the future.
 
+-- kovacs desugars the (a b c : Foo) during parsing (foldr)
+
+-- We need to allow A -> B -> C in functions
+-- We need to handle A -> (A -> B) -> C
+
 ident = token Ident
 
 parens : Parser a -> Parser a
@@ -51,7 +56,7 @@ lit = do
   t <- token Number
   pure $ RLit (LInt (cast t))
 
--- I can haz arrows
+-- typeExpr is term with arrows. 
 export typeExpr : Parser Raw
 export term : (Parser Raw)
 
@@ -64,7 +69,7 @@ atom = withPos (RU <$ keyword "U"
               <|> RVar <$> ident 
               <|> lit
               <|> RHole <$ keyword "_")
-    <|> parens term
+    <|> parens typeExpr
 
 -- Argument to a Spine
 pArg : Parser (Icit,Raw)
@@ -112,7 +117,7 @@ letExpr = do
   commit
   alts <- startBlock $ someSame $ letAssign
   keyword' "in"
-  scope <- term
+  scope <- typeExpr
   
   pure $ foldl (\ acc, (n,v) => RLet n RHole v acc) scope alts
   where
@@ -121,7 +126,7 @@ letExpr = do
       name <- ident
       -- TODO type assertion
       keyword "="
-      t <- term
+      t <- typeExpr
       pure (name,t)
 
 pLetArg : Parser (Icit, String, Maybe Raw)
@@ -138,7 +143,7 @@ lamExpr = do
   commit
   (icit, name, ty) <- pLetArg
   keyword "=>"
-  scope <- term
+  scope <- typeExpr
   -- TODO optional type
   pure $ RLam name icit scope
 

src/Lib/Prettier.idr

@@ -66,6 +66,7 @@ public export
 Semigroup Doc where x <+> y = Seq x (Seq (Text " ") y)
 
 -- Match System.File so we don't get warnings
+public export
 infixl 5 </>
 
 export

src/Lib/TT.idr

@@ -1,4 +1,5 @@
 -- I'm not sure this is related, or just a note to self (Presheaves on Porpoise)
+
 -- maybe watch https://www.youtube.com/watch?v=3gef0_NFz8Q
 -- or drop the indices for now.
 
@@ -7,9 +8,12 @@
 module Lib.TT
 -- For SourcePos
 import Lib.Parser.Impl
+
 import Control.Monad.Error.Interface
 import Data.Fin
 import Data.List
+import Data.Vect
+import Data.SortedMap
 
 public export
 Name : Type
@@ -107,7 +111,8 @@ public export
 ($$) : Closure -> Val -> Val
 ($$) (MkClosure env tm) u = eval (u :: env) tm
 
-infixl 8 $$ 
+public export
+infixl 8 $$
 
 export
 vapp : Val -> Val -> Val
@@ -152,30 +157,69 @@ conv : (lvl : Nat) -> Val -> Val -> Bool
 -- Types = List (Name, Lazy Val)
 
 
+{-
+smalltt
+
+smalltt gets into weird haskell weeds in eval - shifting top level to the left
+and tagging meta vs top with a bit.
+
+I think something subtle is going on with laziness on Elaboration.hs:300
+yeah, and define is even inlined.
+
+So it has a top context, and clears out almost everything for processing a def in
+a different kind of context.
+
+we very much need an idea of local context for metas. I don't want to abstract over
+the entire program.
+
+So I guess we have top and local then?
+
+With haskell syntax. I think we can have Axiom for claims and rewrite to def later.
+
+Hmm, so given ezoo, if I'm going simple, I could keep BDs short, and use the normal
+context. (Zoo4.lean:222) I'd probably still need an undefined/axiom marker as a value? 
+
+ok, so with just one context, Env is List Val and we're getting Tm back from type checking.
+
+Can I get val back? Do we need to quote? What happens if we don't?
+
+-}
+
+data BD = Bound | Defined
+
+-- we'll use this for typechecking, but need to keep a TopContext around too.
 public export
 record Context where
   constructor MkCtx
+  lvl : Nat
+  -- shall we use lvl as an index?
   env : Env                  -- Values in scope
-  types : List (String, Val) -- types and names in scope
-  -- bds  : List BD          -- bind or define
-  -- lvl = length types
+  types : Vect lvl (String, Val) -- types and names in scope
+  -- so we'll try "bds" determines length of local context
+  bds  : List BD          -- bound or defined
+  
   pos : SourcePos            -- the last SourcePos that we saw
 
 export
 empty : Context
-empty = MkCtx [] [] (0,0)
+empty = MkCtx 0 [] [] [] (0,0)
 
 export partial
 Show Context where
   show ctx = "Context \{show $ map fst $ ctx.types}"
 
--- Kovacs Small-TT has locals and globals, lets do that.  
-
 ||| add a binding to environment
 export
 extend : Context -> String -> Val -> Context
-extend (MkCtx env types pos) name ty =
-    MkCtx (VVar (length env) :: env) ((name, ty) :: types) pos
+extend (MkCtx lvl env types bds pos) name ty =
+    MkCtx (S lvl) (VVar lvl :: env) ((name, ty) :: types) (Bound :: bds) pos
+
+-- I guess we define things as values?
+export
+define : Context -> String -> Val -> Val -> Context
+define (MkCtx lvl env types bds pos) name val ty =
+  MkCtx (S lvl) (val :: env) ((name, ty) :: types) (Defined :: bds) pos
+
 
 update : Context -> String -> Tm -> Context
 -- oof
@@ -184,7 +228,7 @@ lookup : {0 m : Type -> Type} -> {auto _ : MonadError String m} ->
       Context -> String -> m Val
 lookup ctx nm = go ctx.types
   where
-    go : List (String,Val) -> m Val
+    go : Vect n (String,Val) -> m Val
     go [] = throwError "Name \{nm} not in scope"
     go ((n, ty) :: xs) = if n == nm then pure ty else go xs
 

src/Lib/TopContext.idr

@@ -0,0 +1,69 @@
+module Lib.TopContext
+
+import Data.String
+import Lib.TT
+
+
+public export
+data Def = Axiom | TCon (List String) | DCon Nat | Fn Tm
+
+Show Def where
+  show Axiom = "axiom"
+  show (TCon strs) = "TCon \{show strs}"
+  show (DCon k) = "DCon \{show k}"
+  show (Fn t) = "Fn \{show t}"
+
+||| entry in the top level context
+public export
+record TopEntry where
+  constructor MkEntry
+  name : String
+  type : Tm
+  def : Def
+
+-- FIXME snoc
+
+export
+Show TopEntry where
+  show (MkEntry name type def) = "\{show name} : \{show type} := \{show def}"
+
+||| Top level context.
+||| Most of the reason this is separate is to have a different type
+||| `Def` for the entries.
+|||
+||| The price is that we have names in addition to levels. Do we want to
+||| expand these during conversion?
+public export
+record TopContext where
+  constructor MkTop
+  -- We'll add a map later?
+  defs : List TopEntry
+
+
+export
+lookup : String -> TopContext -> Maybe TopEntry
+lookup nm top = go top.defs
+  where
+    go : List TopEntry -> Maybe TopEntry
+    go [] = Nothing
+    go (entry :: xs) = if entry.name == nm then Just entry else go xs
+
+-- Maybe pretty print?
+export
+Show TopContext where
+  show (MkTop defs) = "\nContext:\n [\{ joinBy "\n" $ map show defs}]"
+
+public export
+empty : TopContext
+empty = MkTop []
+
+public export
+claim : TopContext -> String -> Tm -> TopContext
+claim tc name ty = { defs $= (MkEntry name ty Axiom ::) } tc
+
+-- TODO update existing, throw, etc.
+
+public export
+addDef : TopContext -> String -> Tm -> Tm -> TopContext
+addDef tc name tm ty = { defs $= (MkEntry name ty (Fn tm) ::) } tc
+