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 Axiom tycons_distinct : ~(ArrowTyCon=ModalBoxTyCon).
19 Variable tyConOrTyFun : CoreTyCon -> sum TyCon TyFun. Extract Inlined Constant tyConOrTyFun => "tyConOrTyFun".
21 Fixpoint coreTypeToWeakType' (ct:CoreType) : ???WeakType :=
23 | TyVarTy cv => match coreVarToWeakVar cv with
24 | WExprVar _ => Error "encountered expression variable in a type"
25 | WTypeVar tv => OK (WTyVarTy tv)
26 | WCoerVar _ => Error "encountered coercion variable in a type"
29 | AppTy t1 t2 => coreTypeToWeakType' t2 >>= fun t2' => coreTypeToWeakType' t1 >>= fun t1' => OK (WAppTy t1' t2')
32 let recurse := ((fix rec tl := match tl with
34 | a::b => coreTypeToWeakType' a >>= fun a' => rec b >>= fun b' => OK (a'::b')
36 in match tyConOrTyFun tc_ with
37 | inr tf => recurse >>= fun recurse' => OK (WTyFunApp tf recurse')
38 | inl tc => if eqd_dec tc ModalBoxTyCon
40 | ((TyVarTy ec)::tbody::nil) =>
41 match coreVarToWeakVar ec with
42 | WTypeVar ec' => coreTypeToWeakType' tbody >>= fun tbody' => OK (WCodeTy ec' tbody')
43 | WExprVar _ => Error "encountered expression variable in a modal box type"
44 | WCoerVar _ => Error "encountered coercion variable in a modal box type"
46 | _ => Error "mis-applied modal box tycon"
48 else let tc' := if eqd_dec tc ArrowTyCon
51 in recurse >>= fun recurse' => OK (fold_left (fun x y => WAppTy x y) recurse' tc')
53 | FunTy (PredTy (EqPred t1 t2)) t3 => coreTypeToWeakType' t1 >>= fun t1' =>
54 coreTypeToWeakType' t2 >>= fun t2' =>
55 coreTypeToWeakType' t3 >>= fun t3' =>
56 OK (WCoFunTy t1' t2' t3')
57 | FunTy t1 t2 => coreTypeToWeakType' t1 >>= fun t1' =>
58 coreTypeToWeakType' t2 >>= fun t2' =>
59 OK (WAppTy (WAppTy WFunTyCon t1') t2')
60 | ForAllTy cv t => match coreVarToWeakVar cv with
61 | WExprVar _ => Error "encountered expression variable in a type"
62 | WTypeVar tv => coreTypeToWeakType' t >>= fun t' => OK (WForAllTy tv t')
63 | WCoerVar _ => Error "encountered coercion variable in a type"
65 | PredTy (ClassP cl lct) => ((fix rec tl := match tl with
67 | a::b => coreTypeToWeakType' a >>= fun a' =>
68 rec b >>= fun b' => OK (a'::b')
69 end) lct) >>= fun lct' => OK (WClassP cl lct')
70 | PredTy (IParam ipn ct) => coreTypeToWeakType' ct >>= fun ct' => OK (WIParam ipn ct')
71 | PredTy (EqPred _ _) => Error "hit a bare EqPred"
74 Variable coreViewDeep : CoreType -> CoreType. Extract Inlined Constant coreViewDeep => "coreViewDeep".
75 Definition coreTypeToWeakType t := coreTypeToWeakType' (coreViewDeep t).
77 (* detects our crude Core-encoding of modal type introduction/elimination forms *)
78 Definition isBrak (ce:@CoreExpr CoreVar) : ??(WeakTypeVar * CoreType) :=
80 | (CoreEApp (CoreEApp (CoreEVar v) (CoreEType (TyVarTy ec))) (CoreEType tbody))
81 => if coreName_eq hetmet_brak_name (coreVarCoreName v) then
82 match coreVarToWeakVar v with
84 | WTypeVar tv => Some (tv,tbody)
89 Definition isEsc (ce:@CoreExpr CoreVar) : ??(WeakTypeVar * CoreType) :=
91 | (CoreEApp (CoreEApp (CoreEVar v) (CoreEType (TyVarTy ec))) (CoreEType tbody))
92 => if coreName_eq hetmet_esc_name (coreVarCoreName v) then
93 match coreVarToWeakVar v with
95 | WTypeVar tv => Some (tv,tbody)
101 Definition coreCoercionToWeakCoercion (cc:CoreCoercion) : ???WeakCoercion :=
102 let (t1,t2) := coreCoercionKind cc
103 in coreTypeToWeakType t1 >>= fun t1' =>
104 coreTypeToWeakType t2 >>= fun t2' =>
105 OK (weakCoercion (kindOfCoreType t1) t1' t2' cc).
107 Fixpoint coreExprToWeakExpr (ce:@CoreExpr CoreVar) : ???WeakExpr :=
109 | CoreELit lit => OK (WELit lit)
110 | CoreENote n e => coreExprToWeakExpr e >>= fun e' => OK (WENote n e')
111 | CoreEType t => Error "encountered CoreEType in a position where an Expr should have been"
112 | CoreECast e co => coreExprToWeakExpr e >>= fun e' =>
113 coreCoercionToWeakCoercion co >>= fun co' =>
116 | CoreEVar v => match coreVarToWeakVar v with
117 | WExprVar ev => OK (WEVar ev)
118 | WTypeVar _ => Error "found a type variable inside an EVar!"
119 | WCoerVar _ => Error "found a coercion variable inside an EVar!"
122 | CoreEApp e1 e2 => match isBrak e1 with
124 coreExprToWeakExpr e2 >>= fun e' =>
125 coreTypeToWeakType t >>= fun t' =>
127 | None => match isEsc e1 with
129 coreExprToWeakExpr e2 >>= fun e' =>
130 coreTypeToWeakType t >>= fun t' =>
132 | None => coreExprToWeakExpr e1 >>= fun e1' =>
135 coreTypeToWeakType t >>= fun t' =>
137 | _ => coreExprToWeakExpr e2 >>= fun e2' => OK (WEApp e1' e2')
142 | CoreELam v e => match coreVarToWeakVar v with
143 | WExprVar ev => coreExprToWeakExpr e >>= fun e' => OK (WELam ev e')
144 | WTypeVar tv => coreExprToWeakExpr e >>= fun e' => OK (WETyLam tv e')
145 | WCoerVar cv => coreExprToWeakExpr e >>= fun e' => OK (WECoLam cv e')
148 | CoreELet (CoreNonRec v ve) e => match coreVarToWeakVar v with
149 | WExprVar ev => coreExprToWeakExpr ve >>= fun ve' =>
150 coreExprToWeakExpr e >>= fun e' => OK (WELet ev ve' e')
151 | WTypeVar _ => match e with
152 | CoreEType t => Error "saw a type-let"
153 | _ => Error "saw (ELet <tyvar> e) where e!=EType"
155 | WCoerVar _ => Error "saw an (ELet <coercionVar>)"
158 | CoreELet (CoreRec rb) e =>
159 ((fix coreExprToWeakExprList (cel:list (CoreVar * (@CoreExpr CoreVar))) : ???(list (WeakExprVar * WeakExpr)) :=
162 | (v',e')::t => coreExprToWeakExprList t >>= fun t' =>
163 match coreVarToWeakVar v' with
164 | WExprVar ev => coreExprToWeakExpr e' >>= fun e' => OK ((ev,e')::t')
165 | WTypeVar _ => Error "found a type variable in a recursive let"
166 | WCoerVar _ => Error "found a coercion variable in a recursive let"
168 end) rb) >>= fun rb' =>
169 coreExprToWeakExpr e >>= fun e' =>
170 OK (WELetRec (unleaves' rb') e')
172 | CoreECase e v tbranches alts =>
173 match coreVarToWeakVar v with
174 | WTypeVar _ => Error "found a type variable in a case"
175 | WCoerVar _ => Error "found a coercion variable in a case"
177 coreExprToWeakExpr e >>= fun e' =>
178 weakTypeOfWeakExpr e' >>= fun te' =>
179 (match isTyConApp te' nil with None => Error "expectTyConApp encountered strange type" | Some x => OK x end)
181 let (tc,lt) := tca in
182 ((fix mkBranches (branches: list (@triple AltCon (list CoreVar) (@CoreExpr CoreVar)))
183 : ???(list (AltCon*list WeakTypeVar*list WeakCoerVar*list WeakExprVar*WeakExpr)) :=
186 | (mkTriple alt vars e)::rest =>
187 mkBranches rest >>= fun rest' =>
188 coreExprToWeakExpr e >>= fun e' =>
190 | DEFAULT => OK ((DEFAULT,nil,nil,nil,e')::rest')
191 | LitAlt lit => OK ((LitAlt lit,nil,nil,nil,e')::rest')
192 | DataAlt dc => let vars := map coreVarToWeakVar vars in
194 (General.filter (map (fun x => match x with WTypeVar v => Some v | _ => None end) vars)),
195 (General.filter (map (fun x => match x with WCoerVar v => Some v | _ => None end) vars)),
196 (General.filter (map (fun x => match x with WExprVar v => Some v | _ => None end) vars)),
201 coreExprToWeakExpr e >>= fun scrutinee =>
202 coreTypeToWeakType tbranches >>= fun tbranches' =>
203 OK (WELet ev scrutinee (WECase (WEVar ev) tbranches' tc lt (unleaves branches)))