view src/corify.sml @ 191:aa54250f58ac

Parametrized datatypes through explify
author Adam Chlipala <adamc@hcoop.net>
date Fri, 08 Aug 2008 10:28:32 -0400
parents 8e9f97508f0d
children 9bbf4d383381
line wrap: on
line source
(* Copyright (c) 2008, Adam Chlipala
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - The names of contributors may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *)

structure Corify :> CORIFY = struct

structure EM = ErrorMsg
structure L = Expl
structure L' = Core

structure IM = IntBinaryMap
structure SM = BinaryMapFn(struct
                           type ord_key = string
                           val compare = String.compare
                           end)

local
    val count = ref 0
in

fun reset v = count := v

fun alloc () =
    let
        val r = !count
    in
        count := r + 1;
        r
end

end

structure St : sig
    type t

    val empty : t

    val debug : t -> unit

    val enter : t -> t
    val leave : t -> {outer : t, inner : t}
    val ffi : string -> L'.con SM.map -> (string * L'.con option * L'.datatype_kind) SM.map -> t

    datatype core_con =
             CNormal of int
           | CFfi of string
    val bindCon : t -> string -> int -> t * int
    val lookupConById : t -> int -> int option
    val lookupConByName : t -> string -> core_con

    val bindConstructor : t -> string -> int -> L'.patCon -> t
    val lookupConstructorByNameOpt : t -> string -> L'.patCon option
    val lookupConstructorByName : t -> string -> L'.patCon
    val lookupConstructorById : t -> int -> L'.patCon

     datatype core_val =
              ENormal of int
            | EFfi of string * L'.con
     val bindVal : t -> string -> int -> t * int
     val bindConstructorVal : t -> string -> int -> t
     val lookupValById : t -> int -> int option
     val lookupValByName : t -> string -> core_val

     val bindStr : t -> string -> int -> t -> t
     val lookupStrById : t -> int -> t
     val lookupStrByName : string * t -> t

     val bindFunctor : t -> string -> int -> string -> int -> L.str -> t
     val lookupFunctorById : t -> int -> string * int * L.str
     val lookupFunctorByName : string * t -> string * int * L.str
 end = struct

 datatype flattening =
          FNormal of {cons : int SM.map,
                      constructors : L'.patCon SM.map,
                      vals : int SM.map,
                      strs : flattening SM.map,
                      funs : (string * int * L.str) SM.map}
        | FFfi of {mod : string,
                   vals : L'.con SM.map,
                   constructors : (string * L'.con option * L'.datatype_kind) SM.map}

 type t = {
      cons : int IM.map,
      constructors : L'.patCon IM.map,
      vals : int IM.map,
      strs : flattening IM.map,
      funs : (string * int * L.str) IM.map,
      current : flattening,
      nested : flattening list
 }

 val empty = {
     cons = IM.empty,
     constructors = IM.empty,
     vals = IM.empty,
     strs = IM.empty,
     funs = IM.empty,
     current = FNormal { cons = SM.empty, constructors = SM.empty, vals = SM.empty, strs = SM.empty, funs = SM.empty },
     nested = []
 }

 fun debug ({current = FNormal {cons, constructors, vals, strs, funs}, ...} : t) =
     print ("cons: " ^ Int.toString (SM.numItems cons) ^ "; "
            ^ "constructors: " ^ Int.toString (SM.numItems constructors) ^ "; "
            ^ "vals: " ^ Int.toString (SM.numItems vals) ^ "; "
            ^ "strs: " ^ Int.toString (SM.numItems strs) ^ "; "
            ^ "funs: " ^ Int.toString (SM.numItems funs) ^ "\n")
   | debug _ = print "Not normal!\n"

 datatype core_con =
          CNormal of int
        | CFfi of string

 datatype core_val =
          ENormal of int
        | EFfi of string * L'.con

 fun bindCon {cons, constructors, vals, strs, funs, current, nested} s n =
     let
         val n' = alloc ()

         val current =
             case current of
                 FFfi _ => raise Fail "Binding inside FFfi"
               | FNormal {cons, constructors, vals, strs, funs} =>
                 FNormal {cons = SM.insert (cons, s, n'),
                          constructors = constructors,
                          vals = vals,
                          strs = strs,
                          funs = funs}
     in
         ({cons = IM.insert (cons, n, n'),
           constructors = constructors,
           vals = vals,
           strs = strs,
           funs = funs,
           current = current,
           nested = nested},
          n')
     end

 fun lookupConById ({cons, ...} : t) n = IM.find (cons, n)

 fun lookupConByName ({current, ...} : t) x =
     case current of
         FFfi {mod = m, ...} => CFfi m
       | FNormal {cons, ...} =>
         case SM.find (cons, x) of
             NONE => raise Fail "Corify.St.lookupConByName"
           | SOME n => CNormal n

 fun bindVal {cons, constructors, vals, strs, funs, current, nested} s n =
     let
         val n' = alloc ()

         val current =
             case current of
                 FFfi _ => raise Fail "Binding inside FFfi"
               | FNormal {cons, constructors, vals, strs, funs} =>
                 FNormal {cons = cons,
                          constructors = constructors,
                          vals = SM.insert (vals, s, n'),
                          strs = strs,
                          funs = funs}
     in
         ({cons = cons,
           constructors = constructors,
           vals = IM.insert (vals, n, n'),
           strs = strs,
           funs = funs,
           current = current,
           nested = nested},
          n')
     end

 fun bindConstructorVal {cons, constructors, vals, strs, funs, current, nested} s n =
     let
         val current =
             case current of
                 FFfi _ => raise Fail "Binding inside FFfi"
               | FNormal {cons, constructors, vals, strs, funs} =>
                 FNormal {cons = cons,
                          constructors = constructors,
                          vals = SM.insert (vals, s, n),
                          strs = strs,
                          funs = funs}
     in
         {cons = cons,
          constructors = constructors,
          vals = IM.insert (vals, n, n),
          strs = strs,
          funs = funs,
          current = current,
          nested = nested}
     end


 fun lookupValById ({vals, ...} : t) n = IM.find (vals, n)

 fun lookupValByName ({current, ...} : t) x =
     case current of
         FFfi {mod = m, vals, ...} =>
         (case SM.find (vals, x) of
              NONE => raise Fail "Corify.St.lookupValByName: no type for FFI val"
            | SOME t => EFfi (m, t))
       | FNormal {vals, ...} =>
         case SM.find (vals, x) of
             NONE => raise Fail "Corify.St.lookupValByName"
           | SOME n => ENormal n

 fun bindConstructor {cons, constructors, vals, strs, funs, current, nested} s n n' =
     let
         val current =
             case current of
                 FFfi _ => raise Fail "Binding inside FFfi"
               | FNormal {cons, constructors, vals, strs, funs} =>
                 FNormal {cons = cons,
                          constructors = SM.insert (constructors, s, n'),
                          vals = vals,
                          strs = strs,
                          funs = funs}
     in
         {cons = cons,
          constructors = IM.insert (constructors, n, n'),
          vals = vals,
          strs = strs,
          funs = funs,
          current = current,
          nested = nested}
     end

 fun lookupConstructorById ({constructors, ...} : t) n =
     case IM.find (constructors, n) of
         NONE => raise Fail "Corify.St.lookupConstructorById"
       | SOME x => x

 fun lookupConstructorByNameOpt ({current, ...} : t) x =
     case current of
         FFfi {mod = m, constructors, ...} =>
         (case SM.find (constructors, x) of
              NONE => NONE
            | SOME (n, to, dk) => SOME (L'.PConFfi {mod = m, datatyp = n, con = x, arg = to, kind = dk}))
       | FNormal {constructors, ...} =>
         case SM.find (constructors, x) of
             NONE => NONE
           | SOME n => SOME n

 fun lookupConstructorByName ({current, ...} : t) x =
     case current of
         FFfi {mod = m, constructors, ...} =>
         (case SM.find (constructors, x) of
              NONE => raise Fail "Corify.St.lookupConstructorByName [1]"
            | SOME (n, to, dk) => L'.PConFfi {mod = m, datatyp = n, con = x, arg = to, kind = dk})
       | FNormal {constructors, ...} =>
         case SM.find (constructors, x) of
             NONE => raise Fail "Corify.St.lookupConstructorByName [2]"
           | SOME n => n

 fun enter {cons, constructors, vals, strs, funs, current, nested} =
     {cons = cons,
      constructors = constructors,
      vals = vals,
      strs = strs,
      funs = funs,
      current = FNormal {cons = SM.empty,
                         constructors = SM.empty,
                         vals = SM.empty,
                         strs = SM.empty,
                         funs = SM.empty},
      nested = current :: nested}

 fun dummy f = {cons = IM.empty,
                constructors = IM.empty,
                vals = IM.empty,
                strs = IM.empty,
                funs = IM.empty,
                current = f,
                nested = []}

 fun leave {cons, constructors, vals, strs, funs, current, nested = m1 :: rest} =
         {outer = {cons = cons,
                   constructors = constructors,
                   vals = vals,
                   strs = strs,
                   funs = funs,
                   current = m1,
                   nested = rest},
          inner = dummy current}
   | leave _ = raise Fail "Corify.St.leave"

 fun ffi m vals constructors = dummy (FFfi {mod = m, vals = vals, constructors = constructors})

 fun bindStr ({cons, constructors, vals, strs, funs,
               current = FNormal {cons = mcons, constructors = mconstructors,
                                  vals = mvals, strs = mstrs, funs = mfuns}, nested} : t)
             x n ({current = f, ...} : t) =
     {cons = cons,
      constructors = constructors,
      vals = vals,
      strs = IM.insert (strs, n, f),
      funs = funs,
      current = FNormal {cons = mcons,
                         constructors = mconstructors,
                         vals = mvals,
                         strs = SM.insert (mstrs, x, f),
                         funs = mfuns},
      nested = nested}
   | bindStr _ _ _ _ = raise Fail "Corify.St.bindStr"

 fun lookupStrById ({strs, ...} : t) n =
     case IM.find (strs, n) of
         NONE => raise Fail "Corify.St.lookupStrById"
       | SOME f => dummy f

 fun lookupStrByName (m, {current = FNormal {strs, ...}, ...} : t) =
     (case SM.find (strs, m) of
          NONE => raise Fail "Corify.St.lookupStrByName"
        | SOME f => dummy f)
   | lookupStrByName _ = raise Fail "Corify.St.lookupStrByName"

 fun bindFunctor ({cons, constructors, vals, strs, funs,
                   current = FNormal {cons = mcons, constructors = mconstructors,
                                      vals = mvals, strs = mstrs, funs = mfuns}, nested} : t)
                 x n xa na str =
     {cons = cons,
      constructors = constructors,
      vals = vals,
      strs = strs,
      funs = IM.insert (funs, n, (xa, na, str)),
      current = FNormal {cons = mcons,
                         constructors = mconstructors,
                         vals = mvals,
                         strs = mstrs,
                         funs = SM.insert (mfuns, x, (xa, na, str))},
      nested = nested}
   | bindFunctor _ _ _ _ _ _ = raise Fail "Corify.St.bindFunctor"

 fun lookupFunctorById ({funs, ...} : t) n =
     case IM.find (funs, n) of
         NONE => raise Fail "Corify.St.lookupFunctorById"
       | SOME v => v

 fun lookupFunctorByName (m, {current = FNormal {funs, ...}, ...} : t) =
     (case SM.find (funs, m) of
          NONE => raise Fail "Corify.St.lookupFunctorByName"
        | SOME v => v)
   | lookupFunctorByName _ = raise Fail "Corify.St.lookupFunctorByName"

 end


 fun corifyKind (k, loc) =
     case k of
         L.KType => (L'.KType, loc)
       | L.KArrow (k1, k2) => (L'.KArrow (corifyKind k1, corifyKind k2), loc)
       | L.KName => (L'.KName, loc)
       | L.KRecord k => (L'.KRecord (corifyKind k), loc)
       | L.KUnit => (L'.KUnit, loc)

 fun corifyCon st (c, loc) =
     case c of
         L.TFun (t1, t2) => (L'.TFun (corifyCon st t1, corifyCon st t2), loc)
       | L.TCFun (x, k, t) => (L'.TCFun (x, corifyKind k, corifyCon st t), loc)
       | L.TRecord c => (L'.TRecord (corifyCon st c), loc)

       | L.CRel n => (L'.CRel n, loc)
       | L.CNamed n =>
         (case St.lookupConById st n of
              NONE => (L'.CNamed n, loc)
            | SOME n => (L'.CNamed n, loc))
       | L.CModProj (m, ms, x) =>
         let
             val st = St.lookupStrById st m
             val st = foldl St.lookupStrByName st ms
         in
             case St.lookupConByName st x of
                 St.CNormal n => (L'.CNamed n, loc)
               | St.CFfi m => (L'.CFfi (m, x), loc)
         end

       | L.CApp (c1, c2) => (L'.CApp (corifyCon st c1, corifyCon st c2), loc)
       | L.CAbs (x, k, c) => (L'.CAbs (x, corifyKind k, corifyCon st c), loc)

       | L.CName s => (L'.CName s, loc)

       | L.CRecord (k, xcs) =>
         (L'.CRecord (corifyKind k, map (fn (c1, c2) => (corifyCon st c1, corifyCon st c2)) xcs), loc)
       | L.CConcat (c1, c2) => (L'.CConcat (corifyCon st c1, corifyCon st c2), loc)
       | L.CFold (k1, k2) => (L'.CFold (corifyKind k1, corifyKind k2), loc)
       | L.CUnit => (L'.CUnit, loc)

 fun corifyPatCon st pc =
     case pc of
         L.PConVar n => St.lookupConstructorById st n
       | L.PConProj (m1, ms, x) =>
         let
             val st = St.lookupStrById st m1
             val st = foldl St.lookupStrByName st ms
         in
             St.lookupConstructorByName st x
         end

 fun corifyPat st (p, loc) =
     case p of
         L.PWild => (L'.PWild, loc)
       | L.PVar (x, t) => (L'.PVar (x, corifyCon st t), loc)
       | L.PPrim p => (L'.PPrim p, loc)
       | L.PCon (dk, pc, ts, po) => raise Fail "Corify PCon" (*(L'.PCon (dk, corifyPatCon st pc, Option.map (corifyPat st) po), loc)*)
       | L.PRecord xps => (L'.PRecord (map (fn (x, p, t) => (x, corifyPat st p, corifyCon st t)) xps), loc)

 fun corifyExp st (e, loc) =
     case e of
         L.EPrim p => (L'.EPrim p, loc)
       | L.ERel n => (L'.ERel n, loc)
       | L.ENamed n =>
         (case St.lookupValById st n of
              NONE => (L'.ENamed n, loc)
            | SOME n => (L'.ENamed n, loc))
       | L.EModProj (m, ms, x) =>
         let
             val st = St.lookupStrById st m
             val st = foldl St.lookupStrByName st ms
         in
             case St.lookupConstructorByNameOpt st x of
                 SOME (pc as L'.PConFfi {mod = m, datatyp, arg, kind, ...}) =>
                 (case arg of
                      NONE => (L'.ECon (kind, pc, NONE), loc)
                    | SOME dom => (L'.EAbs ("x", dom, (L'.CFfi (m, datatyp), loc),
                                            (L'.ECon (kind, pc, SOME (L'.ERel 0, loc)), loc)), loc))
               | _ =>
                 case St.lookupValByName st x of
                     St.ENormal n => (L'.ENamed n, loc)
                   | St.EFfi (m, t) =>
                     case t of
                         (L'.TFun (dom as (L'.TRecord (L'.CRecord (_, []), _), _), ran), _) =>
                         (L'.EAbs ("arg", dom, ran, (L'.EFfiApp (m, x, []), loc)), loc)
                       | t as (L'.TFun _, _) =>
                         let
                             fun getArgs (all as (t, _), args) =
                                 case t of
                                     L'.TFun (dom, ran) => getArgs (ran, dom :: args)
                                   | _ => (all, rev args)

                             val (result, args) = getArgs (t, [])

                             val (actuals, _) = foldr (fn (_, (actuals, n)) =>
                                                          ((L'.ERel n, loc) :: actuals,
                                                           n + 1)) ([], 0) args
                             val app = (L'.EFfiApp (m, x, actuals), loc)
                             val (abs, _, _) = foldr (fn (t, (abs, ran, n)) =>
                                                         ((L'.EAbs ("arg" ^ Int.toString n,
                                                                    t,
                                                                    ran,
                                                                    abs), loc),
                                                          (L'.TFun (t, ran), loc),
                                                          n - 1)) (app, result, length args - 1) args
                         in
                             abs
                         end
                       | _ => (L'.EFfi (m, x), loc)
         end
       | L.EApp (e1, e2) => (L'.EApp (corifyExp st e1, corifyExp st e2), loc)
       | L.EAbs (x, dom, ran, e1) => (L'.EAbs (x, corifyCon st dom, corifyCon st ran, corifyExp st e1), loc)
       | L.ECApp (e1, c) => (L'.ECApp (corifyExp st e1, corifyCon st c), loc)
       | L.ECAbs (x, k, e1) => (L'.ECAbs (x, corifyKind k, corifyExp st e1), loc)

       | L.ERecord xes => (L'.ERecord (map (fn (c, e, t) =>
                                               (corifyCon st c, corifyExp st e, corifyCon st t)) xes), loc)
       | L.EField (e1, c, {field, rest}) => (L'.EField (corifyExp st e1, corifyCon st c,
                                                        {field = corifyCon st field, rest = corifyCon st rest}), loc)
       | L.ECut (e1, c, {field, rest}) => (L'.ECut (corifyExp st e1, corifyCon st c,
                                                    {field = corifyCon st field, rest = corifyCon st rest}), loc)
       | L.EFold k => (L'.EFold (corifyKind k), loc)

       | L.ECase (e, pes, {disc, result}) =>
         (L'.ECase (corifyExp st e,
                    map (fn (p, e) => (corifyPat st p, corifyExp st e)) pes,
                    {disc = corifyCon st disc, result = corifyCon st result}),
          loc)

       | L.EWrite e => (L'.EWrite (corifyExp st e), loc)

 fun corifyDecl ((d, loc : EM.span), st) =
     case d of
         L.DCon (x, n, k, c) =>
         let
             val (st, n) = St.bindCon st x n
         in
             ([(L'.DCon (x, n, corifyKind k, corifyCon st c), loc)], st)
         end
       | L.DDatatype (x, n, xs, xncs) => raise Fail "Corify DDatatype"
         (*let
             val (st, n) = St.bindCon st x n
             val (xncs, st) = ListUtil.foldlMap (fn ((x, n, co), st) =>
                                                    let
                                                        val st = St.bindConstructor st x n (L'.PConVar n)
                                                        val st = St.bindConstructorVal st x n
                                                        val co = Option.map (corifyCon st) co
                                                    in
                                                        ((x, n, co), st)
                                                    end) st xncs

             val dk = CoreUtil.classifyDatatype xncs
             val t = (L'.CNamed n, loc)
             val dcons = map (fn (x, n, to) =>
                                 let
                                     val (e, t) =
                                         case to of
                                             NONE => ((L'.ECon (dk, L'.PConVar n, NONE), loc), t)
                                           | SOME t' => ((L'.EAbs ("x", t', t,
                                                                   (L'.ECon (dk, L'.PConVar n, SOME (L'.ERel 0, loc)),
                                                                    loc)),
                                                          loc),
                                                         (L'.TFun (t', t), loc))
                                 in
                                     (L'.DVal (x, n, t, e, ""), loc)
                                 end) xncs
         in
             ((L'.DDatatype (x, n, xncs), loc) :: dcons, st)
         end*)
       | L.DDatatypeImp (x, n, m1, ms, s, xs, xncs) => raise Fail "Corify DDatatypeImp"
         (*let
             val (st, n) = St.bindCon st x n
             val c = corifyCon st (L.CModProj (m1, ms, s), loc)

             val m = foldl (fn (x, m) => (L.StrProj (m, x), loc)) (L.StrVar m1, loc) ms
             val (_, {inner, ...}) = corifyStr (m, st)

             val (xncs, st) = ListUtil.foldlMap (fn ((x, n, co), st) =>
                                                    let
                                                        val n' = St.lookupConstructorByName inner x
                                                        val st = St.bindConstructor st x n n'
                                                        val (st, n) = St.bindVal st x n
                                                        val co = Option.map (corifyCon st) co
                                                    in
                                                        ((x, n, co), st)
                                                    end) st xncs

             val cds = map (fn (x, n, co) =>
                               let
                                   val t = case co of
                                               NONE => c
                                             | SOME t' => (L'.TFun (t', c), loc)
                                   val e = corifyExp st (L.EModProj (m1, ms, x), loc)
                               in
                                   (L'.DVal (x, n, t, e, x), loc)
                               end) xncs
         in
             ((L'.DCon (x, n, (L'.KType, loc), c), loc) :: cds, st)
         end*)
       | L.DVal (x, n, t, e) =>
         let
             val (st, n) = St.bindVal st x n
             val s =
                 if String.isPrefix "wrap_" x then
                     String.extract (x, 5, NONE)
                 else
                     x
         in
             ([(L'.DVal (x, n, corifyCon st t, corifyExp st e, s), loc)], st)
         end
       | L.DValRec vis =>
         let
             val (vis, st) = ListUtil.foldlMap
                                 (fn ((x, n, t, e), st) =>
                                     let
                                         val (st, n) = St.bindVal st x n
                                     in
                                         ((x, n, t, e), st)
                                     end)
                                 st vis

             val vis = map
                           (fn (x, n, t, e) =>
                               let
                                   val s =
                                       if String.isPrefix "wrap_" x then
                                           String.extract (x, 5, NONE)
                                       else
                                           x
                               in
                                   (x, n, corifyCon st t, corifyExp st e, s)
                               end)
                           vis
         in
             ([(L'.DValRec vis, loc)], st)
         end
       | L.DSgn _ => ([], st)

       | L.DStr (x, n, _, (L.StrFun (xa, na, _, _, str), _)) =>
         ([], St.bindFunctor st x n xa na str)

       | L.DStr (x, n, _, str) =>
         let
             val (ds, {inner, outer}) = corifyStr (str, st)
             val st = St.bindStr outer x n inner
         in
             (ds, st)
         end

       | L.DFfiStr (m, n, (sgn, _)) =>
         (case sgn of
              L.SgnConst sgis =>
              let
                  val (ds, cmap, conmap, st) =
                      foldl (fn ((sgi, _), (ds, cmap, conmap, st)) =>
                                case sgi of
                                    L.SgiConAbs (x, n, k) =>
                                    let
                                        val (st, n') = St.bindCon st x n
                                    in
                                        ((L'.DCon (x, n', corifyKind k, (L'.CFfi (m, x), loc)), loc) :: ds,
                                         cmap,
                                         conmap,
                                         st)
                                    end
                                  | L.SgiCon (x, n, k, _) =>
                                    let
                                        val (st, n') = St.bindCon st x n
                                    in
                                        ((L'.DCon (x, n', corifyKind k, (L'.CFfi (m, x), loc)), loc) :: ds,
                                         cmap,
                                         conmap,
                                         st)
                                    end

                                  | L.SgiDatatype (x, n, xs, xnts) => raise Fail "Corify FFI SgiDatatype"
                                    (*let
                                        val dk = ExplUtil.classifyDatatype xnts
                                        val (st, n') = St.bindCon st x n
                                        val (xnts, (ds', st, cmap, conmap)) =
                                            ListUtil.foldlMap
                                                (fn ((x', n, to), (ds', st, cmap, conmap)) =>
                                                    let
                                                        val dt = (L'.CNamed n', loc)

                                                        val to = Option.map (corifyCon st) to

                                                        val pc = L'.PConFfi {mod = m,
                                                                             datatyp = x,
                                                                             con = x',
                                                                             arg = to,
                                                                             kind = dk}

                                                        val (cmap, d) =
                                                            case to of
                                                                NONE => (SM.insert (cmap, x', dt),
                                                                         (L'.DVal (x', n, dt,
                                                                                   (L'.ECon (dk, pc, NONE), loc),
                                                                                   ""), loc))
                                                              | SOME t =>
                                                                let
                                                                    val tf = (L'.TFun (t, dt), loc)
                                                                    val d = (L'.DVal (x', n, tf,
                                                                                      (L'.EAbs ("x", t, tf,
                                                                                                (L'.ECon (dk, pc,
                                                                                                          SOME (L'.ERel 0,
                                                                                                               loc)),
                                                                                                loc)), loc), ""), loc)
                                                               in
                                                                   (SM.insert (cmap, x', tf), d)
                                                               end

                                                       val st = St.bindConstructor st x' n pc
                                                       (*val st = St.bindConstructorVal st x' n*)

                                                       val conmap = SM.insert (conmap, x', (x, to, dk))
                                                   in
                                                       ((x', n, to),
                                                        (d :: ds', st, cmap, conmap))
                                                   end) ([], st, cmap, conmap) xnts
                                   in
                                       (ds' @ (L'.DDatatype (x, n', xnts), loc) :: ds,
                                        cmap,
                                        conmap,
                                        st)
                                   end*)

                                 | L.SgiVal (x, _, c) =>
                                   (ds,
                                    SM.insert (cmap, x, corifyCon st c),
                                    conmap,
                                    st)
                                 | _ => (ds, cmap, conmap, st)) ([], SM.empty, SM.empty, st) sgis

                 val st = St.bindStr st m n (St.ffi m cmap conmap)
             in
                 (rev ds, st)
             end
           | _ => raise Fail "Non-const signature for FFI structure")

      | L.DExport (en, sgn, str) =>
        (case #1 sgn of
             L.SgnConst sgis =>
             let
                 fun pathify (str, _) =
                     case str of
                         L.StrVar m => SOME (m, [])
                       | L.StrProj (str, s) =>
                         Option.map (fn (m, ms) => (m, ms @ [s])) (pathify str)
                       | _ => NONE
             in
                 case pathify str of
                     NONE => (ErrorMsg.errorAt loc "Structure is too fancy to export";
                              ([], st))
                   | SOME (m, ms) =>
                     let
                         fun wrapSgi ((sgi, _), (wds, eds))  =
                             case sgi of
                                 L.SgiVal (s, _, t as (L.TFun (dom, ran), _)) =>
                                 (case (#1 dom, #1 ran) of
                                      (L.TRecord (L.CRecord (_, []), _),
                                       L.CApp
                                           ((L.CApp
                                                 ((L.CApp ((L.CModProj (_, [], "xml"), _),
                                                           (L.CRecord (_, [((L.CName "Html", _),
                                                                            _)]), _)), _), _), _), _)) =>
                                      let
                                          val ran = (L.TRecord (L.CRecord ((L.KType, loc), []), loc), loc)
                                          val e = (L.EModProj (m, ms, s), loc)
                                          val e = (L.EAbs ("vs", dom, ran,
                                                           (L.EWrite (L.EApp (e, (L.ERel 0, loc)), loc), loc)), loc)
                                      in
                                          ((L.DVal ("wrap_" ^ s, 0,
                                                    (L.TFun (dom, ran), loc),
                                                    e), loc) :: wds,
                                           (fn st =>
                                               case #1 (corifyExp st (L.EModProj (en, [], "wrap_" ^ s), loc)) of
                                                   L'.ENamed n => (L'.DExport (L'.Link, n), loc)
                                                 | _ => raise Fail "Corify: Value to export didn't corify properly")
                                           :: eds)
                                      end
                                    | _ => (wds, eds))
                               | _ => (wds, eds)

                         val (wds, eds) = foldl wrapSgi ([], []) sgis
                         val wrapper = (L.StrConst wds, loc)
                         val (ds, {inner, outer}) = corifyStr (wrapper, st)
                         val st = St.bindStr outer "wrapper" en inner
                         
                         val ds = ds @ map (fn f => f st) eds
                     in
                         (ds, st)
                     end
             end
           | _ => raise Fail "Non-const signature for 'export'")

and corifyStr ((str, _), st) =
    case str of
        L.StrConst ds =>
        let
            val st = St.enter st
            val (ds, st) = ListUtil.foldlMapConcat corifyDecl st ds
        in
            (ds, St.leave st)
        end
      | L.StrVar n => ([], {inner = St.lookupStrById st n, outer = st})
      | L.StrProj (str, x) =>
        let
            val (ds, {inner, outer}) = corifyStr (str, st)
        in
            (ds, {inner = St.lookupStrByName (x, inner), outer = outer})
        end
      | L.StrFun _ => raise Fail "Corify of nested functor definition"
      | L.StrApp (str1, str2) =>
        let
            fun unwind' (str, _) =
                case str of
                    L.StrVar n => St.lookupStrById st n
                  | L.StrProj (str, x) => St.lookupStrByName (x, unwind' str)
                  | _ => raise Fail "Corify of fancy functor application [1]"

            fun unwind (str, _) =
                case str of
                    L.StrVar n => St.lookupFunctorById st n
                  | L.StrProj (str, x) => St.lookupFunctorByName (x, unwind' str)
                  | _ => raise Fail "Corify of fancy functor application [2]"

            val (xa, na, body) = unwind str1

            val (ds1, {inner = inner', outer}) = corifyStr (str2, st)
            val (ds2, {inner, outer}) = corifyStr (body, St.bindStr outer xa na inner')
        in
            (ds1 @ ds2, {inner = St.bindStr inner xa na inner', outer = outer})
        end

fun maxName ds = foldl (fn ((d, _), n) =>
                           case d of
                               L.DCon (_, n', _, _) => Int.max (n, n')
                             | L.DDatatype (_, n', _, _) => Int.max (n, n')
                             | L.DDatatypeImp (_, n', _, _, _, _, _) => Int.max (n, n')
                             | L.DVal (_, n', _, _) => Int.max (n, n')
                             | L.DValRec vis => foldl (fn ((_, n', _, _), n) => Int.max (n, n)) n vis
                             | L.DSgn (_, n', _) => Int.max (n, n')
                             | L.DStr (_, n', _, str) => Int.max (n, Int.max (n', maxNameStr str))
                             | L.DFfiStr (_, n', _) => Int.max (n, n')
                             | L.DExport _ => n)
                 0 ds

and maxNameStr (str, _) =
    case str of
        L.StrConst ds => maxName ds
      | L.StrVar n => n
      | L.StrProj (str, _) => maxNameStr str
      | L.StrFun (_, _, _, _, str) => maxNameStr str
      | L.StrApp (str1, str2) => Int.max (maxNameStr str1, maxNameStr str2)

fun corify ds =
    let
        val () = reset (maxName ds + 1)

        val (ds, _) = ListUtil.foldlMapConcat corifyDecl St.empty ds
    in
        ds
    end

end