HaskFlattener: represent first-order abstraction using GArrows

[coq-hetmet.git] / src / HaskCoreToWeak.v

diff --git a/src/HaskCoreToWeak.v b/src/HaskCoreToWeak.v
index 6e1b58f..78223cf 100644 (file)
--- a/src/HaskCoreToWeak.v
+++ b/src/HaskCoreToWeak.v
@@ -7,7 +7,8 @@ Require Import Preamble.
 Require Import Coq.Lists.List.
 Require Import General.
 Require Import HaskKinds.
-Require Import HaskLiteralsAndTyCons.
+Require Import HaskLiterals.
+Require Import HaskTyCons.
 Require Import HaskCoreVars.
 Require Import HaskCoreTypes.
 Require Import HaskCore.
@@ -53,7 +54,7 @@ Fixpoint coreTypeToWeakType' (ct:CoreType) : ???WeakType :=
                                     | WExprVar _  => Error "encountered expression variable in a modal box type"
                                     | WCoerVar _  => Error "encountered coercion variable in a modal box type"
                                   end
-                                | _                           => Error ("mis-applied modal box tycon: " +++ ct)
+                                | _                           => Error ("mis-applied modal box tycon: " +++ toString ct)
                               end
                          else let tc' := if eqd_dec tc ArrowTyCon
                                          then WFunTyCon
@@ -68,9 +69,11 @@ Fixpoint coreTypeToWeakType' (ct:CoreType) : ???WeakType :=
                                 coreTypeToWeakType' t2 >>= fun t2' => 
                                   OK (WAppTy (WAppTy WFunTyCon t1') t2')
   | ForAllTy cv t            => match coreVarToWeakVar cv with
-                                  | WExprVar _  => Error "encountered expression variable in a type"
+                                  | WExprVar _  => Error "encountered expression variable in a type abstraction"
                                   | WTypeVar tv => coreTypeToWeakType' t >>= fun t' => OK (WForAllTy tv t')
-                                  | WCoerVar _  => Error "encountered coercion variable in a type"
+                                  | WCoerVar (weakCoerVar v t1' t2') => 
+                                        coreTypeToWeakType' t >>= fun t3' => 
+                                          OK (WCoFunTy t1' t2' t3')
                                 end
   | PredTy (ClassP  cl lct) => ((fix rec tl := match tl with 
                                                   | nil => OK nil
@@ -81,7 +84,8 @@ Fixpoint coreTypeToWeakType' (ct:CoreType) : ???WeakType :=
   | PredTy (EqPred _ _)   => Error "hit a bare EqPred"
   end.
 
-Fixpoint coreTypeToWeakType t := addErrorMessage "coreTypeToWeakType" (coreTypeToWeakType' (coreViewDeep t)).
+Definition coreTypeToWeakType t :=
+  addErrorMessage ("during coreTypeToWeakType on " +++ toString t +++ eol) (coreTypeToWeakType' (coreViewDeep t)).
 
 (* detects our crude Core-encoding of modal type introduction/elimination forms *)
 Definition isBrak (ce:@CoreExpr CoreVar) : ??(WeakExprVar * WeakTypeVar * CoreType) :=
@@ -134,8 +138,8 @@ Fixpoint expectTyConApp (wt:WeakType)(acc:list WeakType) : ???(TyCon * list Weak
   match wt with
     | WTyCon tc        => OK (tc,acc)
     | WAppTy t1 t2     => expectTyConApp t1 (t2::acc)
-    | WTyFunApp tc tys => Error ("expectTyConApp encountered TyFunApp: " +++ wt)
-    | _                => Error ("expectTyConApp encountered " +++ wt)
+    | WTyFunApp tc tys => Error ("expectTyConApp encountered TyFunApp: " +++ toString wt)
+    | _                => Error ("expectTyConApp encountered " +++ toString wt)
   end.
 
 Fixpoint coreExprToWeakExpr (ce:@CoreExpr CoreVar) : ???WeakExpr :=