1 (*********************************************************************************************************************************)
2 (* HaskCoreToWeak: convert HaskCore to HaskWeak *)
3 (*********************************************************************************************************************************)
5 Generalizable All Variables.
6 Require Import Preamble.
7 Require Import General.
8 Require Import Coq.Lists.List.
9 Require Import HaskKinds.
10 Require Import HaskCoreLiterals.
11 Require Import HaskCoreVars.
12 Require Import HaskCoreTypes.
13 Require Import HaskCore.
14 Require Import HaskWeakVars.
15 Require Import HaskWeakTypes.
16 Require Import HaskWeak.
18 Variable tyConOrTyFun : CoreTyCon -> sum TyCon TyFun. Extract Inlined Constant tyConOrTyFun => "tyConOrTyFun".
19 Variable coreViewDeep : CoreType -> CoreType. Extract Inlined Constant coreViewDeep => "coreViewDeep".
20 Variable coreCoercionToWeakCoercion : CoreCoercion -> WeakCoercion.
21 Extract Inlined Constant coreCoercionToWeakCoercion => "coreCoercionToWeakCoercion".
23 (* extracts the Name from a CoreVar *)
24 Variable coreVarCoreName : CoreVar -> CoreName. Extract Inlined Constant coreVarCoreName => "Var.varName".
26 (* the magic wired-in name for the modal type introduction form *)
27 Variable hetmet_brak_name : CoreName. Extract Inlined Constant hetmet_brak_name => "PrelNames.hetmet_brak_name".
29 (* the magic wired-in name for the modal type elimination form *)
30 Variable hetmet_esc_name : CoreName. Extract Inlined Constant hetmet_esc_name => "PrelNames.hetmet_esc_name".
32 Fixpoint coreTypeToWeakType' (ct:CoreType) : ???WeakType :=
34 | TyVarTy cv => match coreVarToWeakVar cv with
35 | WExprVar _ => Error "encountered expression variable in a type"
36 | WTypeVar tv => OK (WTyVarTy tv)
37 | WCoerVar _ => Error "encountered coercion variable in a type"
40 | AppTy t1 t2 => coreTypeToWeakType' t2 >>= fun t2' => coreTypeToWeakType' t1 >>= fun t1' => OK (WAppTy t1' t2')
43 let recurse := ((fix rec tl := match tl with
45 | a::b => coreTypeToWeakType' a >>= fun a' => rec b >>= fun b' => OK (a'::b')
47 in match tyConOrTyFun tc_ with
48 | inr tf => recurse >>= fun recurse' => OK (WTyFunApp tf recurse')
49 | inl tc => if eqd_dec tc ModalBoxTyCon
51 | ((TyVarTy ec)::tbody::nil) =>
52 match coreVarToWeakVar ec with
53 | WTypeVar ec' => coreTypeToWeakType' tbody >>= fun tbody' => OK (WCodeTy ec' tbody')
54 | WExprVar _ => Error "encountered expression variable in a modal box type"
55 | WCoerVar _ => Error "encountered coercion variable in a modal box type"
57 | _ => Error ("mis-applied modal box tycon: " +++ ct)
59 else let tc' := if eqd_dec tc ArrowTyCon
62 in recurse >>= fun recurse' => OK (fold_left (fun x y => WAppTy x y) recurse' tc')
64 | FunTy (PredTy (EqPred t1 t2)) t3 => coreTypeToWeakType' t1 >>= fun t1' =>
65 coreTypeToWeakType' t2 >>= fun t2' =>
66 coreTypeToWeakType' t3 >>= fun t3' =>
67 OK (WCoFunTy t1' t2' t3')
68 | FunTy t1 t2 => coreTypeToWeakType' t1 >>= fun t1' =>
69 coreTypeToWeakType' t2 >>= fun t2' =>
70 OK (WAppTy (WAppTy WFunTyCon t1') t2')
71 | ForAllTy cv t => match coreVarToWeakVar cv with
72 | WExprVar _ => Error "encountered expression variable in a type"
73 | WTypeVar tv => coreTypeToWeakType' t >>= fun t' => OK (WForAllTy tv t')
74 | WCoerVar _ => Error "encountered coercion variable in a type"
76 | PredTy (ClassP cl lct) => ((fix rec tl := match tl with
78 | a::b => coreTypeToWeakType' a >>= fun a' =>
79 rec b >>= fun b' => OK (a'::b')
80 end) lct) >>= fun lct' => OK (WClassP cl lct')
81 | PredTy (IParam ipn ct) => coreTypeToWeakType' ct >>= fun ct' => OK (WIParam ipn ct')
82 | PredTy (EqPred _ _) => Error "hit a bare EqPred"
85 Fixpoint coreTypeToWeakType t := addErrorMessage "coreTypeToWeakType" (coreTypeToWeakType' (coreViewDeep t)).
87 (* detects our crude Core-encoding of modal type introduction/elimination forms *)
88 Definition isBrak (ce:@CoreExpr CoreVar) : ??(CoreVar * WeakTypeVar * CoreType) :=
90 | (CoreEApp (CoreEApp (CoreEVar v) (CoreEType (TyVarTy ec))) (CoreEType tbody))
91 => if coreName_eq hetmet_brak_name (coreVarCoreName v) then
92 match coreVarToWeakVar ec with
94 | WTypeVar tv => Some (v,tv,tbody)
100 Definition isEsc (ce:@CoreExpr CoreVar) : ??(CoreVar * WeakTypeVar * CoreType) :=
102 | (CoreEApp (CoreEApp (CoreEVar v) (CoreEType (TyVarTy ec))) (CoreEType tbody))
103 => if coreName_eq hetmet_esc_name (coreVarCoreName v) then
104 match coreVarToWeakVar ec with
106 | WTypeVar tv => Some (v,tv,tbody)
112 (* if this is a (WAppTy (WAppTy ... (WTyCon tc) .. ) .. ), return (tc,[...]) *)
113 Fixpoint expectTyConApp (wt:WeakType)(acc:list WeakType) : ???(TyCon * list WeakType) :=
115 | WTyCon tc => OK (tc,acc)
116 | WAppTy t1 t2 => expectTyConApp t1 (t2::acc)
117 | WTyFunApp tc tys => Error ("expectTyConApp encountered TyFunApp: " +++ wt)
118 | _ => Error ("expectTyConApp encountered " +++ wt)
121 Fixpoint coreExprToWeakExpr (ce:@CoreExpr CoreVar) : ???WeakExpr :=
123 | CoreELit lit => OK (WELit lit)
124 | CoreENote n e => coreExprToWeakExpr e >>= fun e' => OK (WENote n e')
125 | CoreEType t => Error "encountered CoreEType in a position where an Expr should have been"
126 | CoreECast e co => coreExprToWeakExpr e >>= fun e' =>
127 OK (WECast e' (coreCoercionToWeakCoercion co))
129 | CoreEVar v => match coreVarToWeakVar v with
130 | WExprVar ev => OK (WEVar ev)
131 | WTypeVar _ => Error "found a type variable inside an EVar!"
132 | WCoerVar _ => Error "found a coercion variable inside an EVar!"
135 | CoreEApp e1 e2 => match isBrak e1 with
137 coreExprToWeakExpr e2 >>= fun e' =>
138 coreTypeToWeakType t >>= fun t' =>
139 OK (WEBrak v tv e' t')
140 | None => match isEsc e1 with
142 coreExprToWeakExpr e2 >>= fun e' =>
143 coreTypeToWeakType t >>= fun t' =>
144 OK (WEEsc v tv e' t')
145 | None => coreExprToWeakExpr e1 >>= fun e1' =>
148 coreTypeToWeakType t >>= fun t' =>
150 | _ => coreExprToWeakExpr e2 >>= fun e2' => OK (WEApp e1' e2')
155 | CoreELam v e => match coreVarToWeakVar v with
156 | WExprVar ev => coreExprToWeakExpr e >>= fun e' => OK (WELam ev e')
157 | WTypeVar tv => coreExprToWeakExpr e >>= fun e' => OK (WETyLam tv e')
158 | WCoerVar cv => coreExprToWeakExpr e >>= fun e' => OK (WECoLam cv e')
161 | CoreELet (CoreNonRec v ve) e => match coreVarToWeakVar v with
162 | WExprVar ev => coreExprToWeakExpr ve >>= fun ve' =>
163 coreExprToWeakExpr e >>= fun e' => OK (WELet ev ve' e')
164 | WTypeVar _ => match e with
165 | CoreEType t => Error "saw a type-let"
166 | _ => Error "saw (ELet <tyvar> e) where e!=EType"
168 | WCoerVar _ => Error "saw an (ELet <coercionVar>)"
171 | CoreELet (CoreRec rb) e =>
172 ((fix coreExprToWeakExprList (cel:list (CoreVar * (@CoreExpr CoreVar))) : ???(list (WeakExprVar * WeakExpr)) :=
175 | (v',e')::t => coreExprToWeakExprList t >>= fun t' =>
176 match coreVarToWeakVar v' with
177 | WExprVar ev => coreExprToWeakExpr e' >>= fun e' => OK ((ev,e')::t')
178 | WTypeVar _ => Error "found a type variable in a recursive let"
179 | WCoerVar _ => Error "found a coercion variable in a recursive let"
181 end) rb) >>= fun rb' =>
182 coreExprToWeakExpr e >>= fun e' =>
183 OK (WELetRec (unleaves' rb') e')
185 | CoreECase e v tbranches alts =>
186 match coreVarToWeakVar v with
187 | WTypeVar _ => Error "found a type variable in a case"
188 | WCoerVar _ => Error "found a coercion variable in a case"
190 coreTypeToWeakType (coreTypeOfCoreExpr e) >>= fun te' =>
191 coreExprToWeakExpr e >>= fun e' =>
192 expectTyConApp te' nil >>= fun tca =>
193 let (tc,lt) := tca in
194 ((fix mkBranches (branches: list (@triple AltCon (list CoreVar) (@CoreExpr CoreVar)))
195 : ???(list (AltCon*list WeakTypeVar*list WeakCoerVar*list WeakExprVar*WeakExpr)) :=
198 | (mkTriple alt vars e)::rest =>
199 mkBranches rest >>= fun rest' =>
200 coreExprToWeakExpr e >>= fun e' =>
202 | DEFAULT => OK ((DEFAULT,nil,nil,nil,e')::rest')
203 | LitAlt lit => OK ((LitAlt lit,nil,nil,nil,e')::rest')
204 | DataAlt dc => let vars := map coreVarToWeakVar vars in
206 (General.filter (map (fun x => match x with WTypeVar v => Some v | _ => None end) vars)),
207 (General.filter (map (fun x => match x with WCoerVar v => Some v | _ => None end) vars)),
208 (General.filter (map (fun x => match x with WExprVar v => Some v | _ => None end) vars)),
213 coreExprToWeakExpr e >>= fun scrutinee =>
214 coreTypeToWeakType tbranches >>= fun tbranches' =>
215 OK (WECase ev scrutinee tbranches' tc lt (unleaves branches))