adamc@81: (* Copyright (c) 2008, Adam Chlipala
adamc@81:  * All rights reserved.
adamc@81:  *
adamc@81:  * Redistribution and use in source and binary forms, with or without
adamc@81:  * modification, are permitted provided that the following conditions are met:
adamc@81:  *
adamc@81:  * - Redistributions of source code must retain the above copyright notice,
adamc@81:  *   this list of conditions and the following disclaimer.
adamc@81:  * - Redistributions in binary form must reproduce the above copyright notice,
adamc@81:  *   this list of conditions and the following disclaimer in the documentation
adamc@81:  *   and/or other materials provided with the distribution.
adamc@81:  * - The names of contributors may not be used to endorse or promote products
adamc@81:  *   derived from this software without specific prior written permission.
adamc@81:  *
adamc@81:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@81:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@81:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@81:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@81:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
adamc@81:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@81:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@81:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@81:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@81:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@81:  * POSSIBILITY OF SUCH DAMAGE.
adamc@81:  *)
adamc@81: 
adamc@81: structure ElabOps :> ELAB_OPS = struct
adamc@81: 
adamc@81: open Elab
adamc@81: 
adamc@81: structure E = ElabEnv
adamc@81: structure U = ElabUtil
adamc@81: 
adamc@81: val liftConInCon = E.liftConInCon
adamc@81: 
adamc@81: val subConInCon =
adamc@81:     U.Con.mapB {kind = fn k => k,
adamc@81:                 con = fn (xn, rep) => fn c =>
adamc@81:                                   case c of
adamc@81:                                       CRel xn' =>
adamc@81:                                       (case Int.compare (xn', xn) of
adamc@81:                                            EQUAL => #1 rep
adamc@81:                                          | GREATER => CRel (xn' - 1)
adamc@81:                                          | LESS => c)
adamc@81:                                     (*| CUnif _ => raise SynUnif*)
adamc@81:                                     | _ => c,
adamc@81:                 bind = fn ((xn, rep), U.Con.Rel _) => (xn+1, liftConInCon 0 rep)
adamc@81:                         | (ctx, _) => ctx}
adamc@81: 
adamc@81: fun subStrInSgn (m1, m2) =
adamc@81:     U.Sgn.map {kind = fn k => k,
adamc@81:                con = fn c as CModProj (m1', ms, x) =>
adamc@81:                         if m1 = m1' then
adamc@81:                             CModProj (m2, ms, x)
adamc@81:                         else
adamc@81:                             c
adamc@81:                       | c => c,
adamc@81:                sgn_item = fn sgi => sgi,
adamc@81:                sgn = fn sgn => sgn}
adamc@81: 
adamc@81: 
adamc@81: fun hnormCon env (cAll as (c, loc)) =
adamc@81:     case c of
adamc@81:         CUnif (_, _, _, ref (SOME c)) => hnormCon env c
adamc@81: 
adamc@81:       | CNamed xn =>
adamc@81:         (case E.lookupCNamed env xn of
adamc@81:              (_, _, SOME c') => hnormCon env c'
adamc@81:            | _ => cAll)
adamc@81: 
adamc@81:       | CModProj (n, ms, x) =>
adamc@81:         let
adamc@81:             val (_, sgn) = E.lookupStrNamed env n
adamc@81:             val (str, sgn) = foldl (fn (m, (str, sgn)) =>
adamc@81:                                        case E.projectStr env {sgn = sgn, str = str, field = m} of
adamc@81:                                            NONE => raise Fail "hnormCon: Unknown substructure"
adamc@81:                                          | SOME sgn => ((StrProj (str, m), loc), sgn))
adamc@81:                              ((StrVar n, loc), sgn) ms
adamc@81:         in
adamc@81:             case E.projectCon env {sgn = sgn, str = str, field = x} of
adamc@81:                 NONE => raise Fail "kindof: Unknown con in structure"
adamc@81:               | SOME (_, NONE) => cAll
adamc@81:               | SOME (_, SOME c) => hnormCon env c
adamc@81:         end
adamc@81: 
adamc@81:       | CApp (c1, c2) =>
adamc@81:         (case #1 (hnormCon env c1) of
adamc@81:              CAbs (x, k, cb) =>
adamc@81:              let
adamc@81:                  val sc = (hnormCon env (subConInCon (0, c2) cb))
adamc@81:                      handle SynUnif => cAll
adamc@81:                  (*val env' = E.pushCRel env x k*)
adamc@81:              in
adamc@328:                  (*Print.eprefaces "Subst" [("x", Print.PD.string x),
adamc@328:                                           ("cb", ElabPrint.p_con env' cb),
adamc@328:                                           ("c2", ElabPrint.p_con env c2),
adamc@328:                                           ("sc", ElabPrint.p_con env sc)];*)
adamc@81:                  sc
adamc@81:              end
adamc@326:            | c1' as CApp (c', i) =>
adamc@326:              let
adamc@326:                  fun default () = (CApp ((c1', loc), hnormCon env c2), loc)
adamc@326:              in
adamc@326:                  case #1 (hnormCon env c') of
adamc@326:                      CApp (c', f) =>
adamc@326:                      (case #1 (hnormCon env c') of
adamc@326:                           CFold ks =>
adamc@326:                           (case #1 (hnormCon env c2) of
adamc@326:                                CRecord (_, []) => hnormCon env i
adamc@326:                              | CRecord (k, (x, c) :: rest) =>
adamc@326:                                hnormCon env
adamc@326:                                         (CApp ((CApp ((CApp (f, x), loc), c), loc),
adamc@81:                                                (CApp ((CApp ((CApp ((CFold ks, loc), f), loc), i), loc),
adamc@326:                                                       (CRecord (k, rest), loc)), loc)), loc)
adamc@326:                              | CConcat ((CRecord (k, (x, c) :: rest), _), rest') =>
adamc@326:                                let
adamc@326:                                    val rest'' = (CConcat ((CRecord (k, rest), loc), rest'), loc)
adamc@81: 
adamc@326:                                (*val ccc = (CApp ((CApp ((CApp (f, x), loc), c), loc),
adamc@326:                                                   (CApp ((CApp ((CApp ((CFold ks, loc), f), loc), i), loc),
adamc@326:                                                          rest''), loc)), loc)*)
adamc@326:                                in
adamc@326:                                    (*eprefaces "Red to" [("ccc", p_con env ccc), ("ccc'", p_con env (hnormCon env ccc))];*)
adamc@326:                                    hnormCon env
adamc@326:                                             (CApp ((CApp ((CApp (f, x), loc), c), loc),
adamc@81:                                                    (CApp ((CApp ((CApp ((CFold ks, loc), f), loc), i), loc),
adamc@326:                                                           rest''), loc)), loc)
adamc@326:                                end
adamc@329:                              | _ =>
adamc@329:                                let
adamc@329:                                    fun cunif () =
adamc@329:                                        let
adamc@329:                                            val r = ref NONE
adamc@329:                                        in
adamc@329:                                            (r, (CUnif (loc, (KType, loc), "_", r), loc))
adamc@329:                                        end
adamc@329: 
adamc@329:                                    val (nmR, nm) = cunif ()
adamc@329:                                    val (vR, v) = cunif ()
adamc@329:                                    val (rR, r) = cunif ()
adamc@329: 
adamc@329:                                    val c = f
adamc@329:                                    val c = (CApp (c, nm), loc)
adamc@329:                                    val c = (CApp (c, v), loc)
adamc@329:                                    val c = (CApp (c, r), loc)
adamc@329:                                    fun unconstraint c =
adamc@329:                                        case hnormCon env c of
adamc@329:                                            (CDisjoint (_, _, c), _) => unconstraint c
adamc@329:                                          | c => c
adamc@329:                                    val c = unconstraint c
adamc@329:                                in
adamc@329:                                    (*Print.prefaces "Consider" [("c", ElabPrint.p_con env c)];*)
adamc@329:                                    case (hnormCon env i, unconstraint c) of
adamc@329:                                        ((CRecord (_, []), _),
adamc@329:                                         (CConcat (c1, c2'), _)) =>
adamc@329:                                        (case (hnormCon env c1, hnormCon env c2') of
adamc@329:                                             ((CRecord (_, [(nm', v')]), _),
adamc@329:                                              (CUnif (_, _, _, rR'), _)) =>
adamc@329:                                             (case (hnormCon env nm', hnormCon env v') of
adamc@329:                                                  ((CUnif (_, _, _, nmR'), _),
adamc@329:                                                   (CUnif (_, _, _, vR'), _)) =>
adamc@329:                                                  if nmR' = nmR andalso vR' = vR andalso rR' = rR then
adamc@329:                                                      hnormCon env c2
adamc@329:                                                  else
adamc@329:                                                      default ()
adamc@329:                                                | _ => default ())
adamc@329:                                           | _ => default ())
adamc@329:                                      | _ => default ()
adamc@329:                                end)
adamc@326:                         | _ => default ())
adamc@326:                    | _ => default ()
adamc@326:              end
adamc@326:            | c1' => (CApp ((c1', loc), hnormCon env c2), loc))
adamc@81: 
adamc@81:       | CConcat (c1, c2) =>
adamc@81:         (case (hnormCon env c1, hnormCon env c2) of
adamc@81:              ((CRecord (k, xcs1), loc), (CRecord (_, xcs2), _)) =>
adamc@81:              (CRecord (k, xcs1 @ xcs2), loc)
adamc@81:            | ((CRecord (_, []), _), c2') => c2'
adamc@81:            | ((CConcat (c11, c12), loc), c2') =>
adamc@81:              hnormCon env (CConcat (c11, (CConcat (c12, c2'), loc)), loc)
adamc@209:            | (c1', (CRecord (_, []), _)) => c1'
adamc@329:            | (c1', c2') => (CConcat (c1', c2'), loc))
adamc@81: 
adamc@207:       | CProj (c, n) =>
adamc@207:         (case hnormCon env c of
adamc@207:              (CTuple cs, _) => hnormCon env (List.nth (cs, n - 1))
adamc@207:            | _ => cAll)
adamc@207: 
adamc@81:       | _ => cAll
adamc@81: 
adamc@81: end