adamc@2: (* Copyright (c) 2008, Adam Chlipala
adamc@2:  * All rights reserved.
adamc@2:  *
adamc@2:  * Redistribution and use in source and binary forms, with or without
adamc@2:  * modification, are permitted provided that the following conditions are met:
adamc@2:  *
adamc@2:  * - Redistributions of source code must retain the above copyright notice,
adamc@2:  *   this list of conditions and the following disclaimer.
adamc@2:  * - Redistributions in binary form must reproduce the above copyright notice,
adamc@2:  *   this list of conditions and the following disclaimer in the documentation
adamc@2:  *   and/or other materials provided with the distribution.
adamc@2:  * - The names of contributors may not be used to endorse or promote products
adamc@2:  *   derived from this software without specific prior written permission.
adamc@2:  *
adamc@2:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@2:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@2:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@2:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@2:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
adamc@2:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@2:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@2:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@2:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@2:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@2:  * POSSIBILITY OF SUCH DAMAGE.
adamc@2:  *)
adamc@2: 
adamc@2: structure ElabEnv :> ELAB_ENV = struct
adamc@2: 
adamc@2: open Elab
adamc@2: 
adamc@13: structure U = ElabUtil
adamc@13: 
adamc@2: structure IM = IntBinaryMap
adamc@2: structure SM = BinaryMapFn(struct
adamc@2:                            type ord_key = string
adamc@2:                            val compare = String.compare
adamc@2:                            end)
adamc@2: 
adamc@2: exception UnboundRel of int
adamc@2: exception UnboundNamed of int
adamc@2: 
adamc@13: 
adamc@13: (* AST utility functions *)
adamc@13: 
adamc@13: exception SynUnif
adamc@13: 
adamc@13: val liftConInCon =
adamc@13:     U.Con.mapB {kind = fn k => k,
adamc@13:                 con = fn bound => fn c =>
adamc@13:                                      case c of
adamc@16:                                          CRel xn =>
adamc@13:                                          if xn < bound then
adamc@13:                                              c
adamc@13:                                          else
adamc@16:                                              CRel (xn + 1)
adamc@17:                                        (*| CUnif _ => raise SynUnif*)
adamc@13:                                        | _ => c,
adamc@13:                 bind = fn (bound, U.Con.Rel _) => bound + 1
adamc@13:                         | (bound, _) => bound}
adamc@13: 
adamc@13: val lift = liftConInCon 0
adamc@13: 
adamc@13: 
adamc@13: (* Back to environments *)
adamc@13: 
adamc@9: datatype 'a var' =
adamc@9:          Rel' of int * 'a
adamc@9:        | Named' of int * 'a
adamc@2: 
adamc@9: datatype 'a var =
adamc@9:          NotBound
adamc@9:        | Rel of int * 'a
adamc@9:        | Named of int * 'a
adamc@2: 
adamc@2: type env = {
adamc@9:      renameC : kind var' SM.map,
adamc@2:      relC : (string * kind) list,
adamc@11:      namedC : (string * kind * con option) IM.map,
adamc@9: 
adamc@9:      renameE : con var' SM.map,
adamc@9:      relE : (string * con) list,
adamc@31:      namedE : (string * con) IM.map,
adamc@31: 
adamc@31:      renameSgn : (int * sgn) SM.map,
adamc@31:      sgn : (string * sgn) IM.map,
adamc@31: 
adamc@31:      renameStr : (int * sgn) SM.map,
adamc@31:      str : (string * sgn) IM.map
adamc@2: }
adamc@2: 
adamc@2: val namedCounter = ref 0
adamc@2: 
adamc@2: val empty = {
adamc@2:     renameC = SM.empty,
adamc@2:     relC = [],
adamc@9:     namedC = IM.empty,
adamc@9: 
adamc@9:     renameE = SM.empty,
adamc@9:     relE = [],
adamc@31:     namedE = IM.empty,
adamc@31: 
adamc@31:     renameSgn = SM.empty,
adamc@31:     sgn = IM.empty,
adamc@31: 
adamc@31:     renameStr = SM.empty,
adamc@31:     str = IM.empty
adamc@2: }
adamc@2: 
adamc@2: fun pushCRel (env : env) x k =
adamc@2:     let
adamc@9:         val renameC = SM.map (fn Rel' (n, k) => Rel' (n+1, k)
adamc@2:                                | x => x) (#renameC env)
adamc@2:     in
adamc@9:         {renameC = SM.insert (renameC, x, Rel' (0, k)),
adamc@2:          relC = (x, k) :: #relC env,
adamc@13:          namedC = IM.map (fn (x, k, co) => (x, k, Option.map lift co)) (#namedC env),
adamc@9: 
adamc@9:          renameE = #renameE env,
adamc@13:          relE = map (fn (x, c) => (x, lift c)) (#relE env),
adamc@31:          namedE = IM.map (fn (x, c) => (x, lift c)) (#namedE env),
adamc@31: 
adamc@31:          renameSgn = #renameSgn env,
adamc@31:          sgn = #sgn env,
adamc@31: 
adamc@31:          renameStr = #renameStr env,
adamc@31:          str = #str env
adamc@31:         }
adamc@2:     end
adamc@2: 
adamc@2: fun lookupCRel (env : env) n =
adamc@2:     (List.nth (#relC env, n))
adamc@2:     handle Subscript => raise UnboundRel n
adamc@2: 
adamc@11: fun pushCNamedAs (env : env) x n k co =
adamc@9:     {renameC = SM.insert (#renameC env, x, Named' (n, k)),
adamc@5:      relC = #relC env,
adamc@11:      namedC = IM.insert (#namedC env, n, (x, k, co)),
adamc@9: 
adamc@9:      renameE = #renameE env,
adamc@9:      relE = #relE env,
adamc@31:      namedE = #namedE env,
adamc@31: 
adamc@31:      renameSgn = #renameSgn env,
adamc@31:      sgn = #sgn env,
adamc@31:      
adamc@31:      renameStr = #renameStr env,
adamc@31:      str = #str env}
adamc@5: 
adamc@11: fun pushCNamed env x k co =
adamc@2:     let
adamc@2:         val n = !namedCounter
adamc@2:     in
adamc@2:         namedCounter := n + 1;
adamc@11:         (pushCNamedAs env x n k co, n)
adamc@2:     end
adamc@2: 
adamc@2: fun lookupCNamed (env : env) n =
adamc@2:     case IM.find (#namedC env, n) of
adamc@2:         NONE => raise UnboundNamed n
adamc@2:       | SOME x => x
adamc@2: 
adamc@2: fun lookupC (env : env) x =
adamc@2:     case SM.find (#renameC env, x) of
adamc@9:         NONE => NotBound
adamc@9:       | SOME (Rel' x) => Rel x
adamc@9:       | SOME (Named' x) => Named x
adamc@9: 
adamc@9: fun pushERel (env : env) x t =
adamc@9:     let
adamc@9:         val renameE = SM.map (fn Rel' (n, t) => Rel' (n+1, t)
adamc@9:                                | x => x) (#renameE env)
adamc@9:     in
adamc@9:         {renameC = #renameC env,
adamc@9:          relC = #relC env,
adamc@9:          namedC = #namedC env,
adamc@9: 
adamc@9:          renameE = SM.insert (renameE, x, Rel' (0, t)),
adamc@9:          relE = (x, t) :: #relE env,
adamc@31:          namedE = #namedE env,
adamc@31: 
adamc@31:          renameSgn = #renameSgn env,
adamc@31:          sgn = #sgn env,
adamc@31: 
adamc@31:          renameStr = #renameStr env,
adamc@31:          str = #str env}
adamc@9:     end
adamc@9: 
adamc@9: fun lookupERel (env : env) n =
adamc@9:     (List.nth (#relE env, n))
adamc@9:     handle Subscript => raise UnboundRel n
adamc@9: 
adamc@9: fun pushENamedAs (env : env) x n t =
adamc@9:     {renameC = #renameC env,
adamc@9:      relC = #relC env,
adamc@9:      namedC = #namedC env,
adamc@9: 
adamc@9:      renameE = SM.insert (#renameE env, x, Named' (n, t)),
adamc@9:      relE = #relE env,
adamc@31:      namedE = IM.insert (#namedE env, n, (x, t)),
adamc@31: 
adamc@31:      renameSgn = #renameSgn env,
adamc@31:      sgn = #sgn env,
adamc@31:      
adamc@31:      renameStr = #renameStr env,
adamc@31:      str = #str env}
adamc@9: 
adamc@9: fun pushENamed env x t =
adamc@9:     let
adamc@9:         val n = !namedCounter
adamc@9:     in
adamc@9:         namedCounter := n + 1;
adamc@9:         (pushENamedAs env x n t, n)
adamc@9:     end
adamc@9: 
adamc@9: fun lookupENamed (env : env) n =
adamc@9:     case IM.find (#namedE env, n) of
adamc@9:         NONE => raise UnboundNamed n
adamc@9:       | SOME x => x
adamc@9: 
adamc@9: fun lookupE (env : env) x =
adamc@9:     case SM.find (#renameE env, x) of
adamc@9:         NONE => NotBound
adamc@9:       | SOME (Rel' x) => Rel x
adamc@9:       | SOME (Named' x) => Named x
adamc@2: 
adamc@31: fun pushSgnNamedAs (env : env) x n sgis =
adamc@31:     {renameC = #renameC env,
adamc@31:      relC = #relC env,
adamc@31:      namedC = #namedC env,
adamc@31: 
adamc@31:      renameE = #renameE env,
adamc@31:      relE = #relE env,
adamc@31:      namedE = #namedE env,
adamc@31: 
adamc@31:      renameSgn = SM.insert (#renameSgn env, x, (n, sgis)),
adamc@31:      sgn = IM.insert (#sgn env, n, (x, sgis)),
adamc@31:      
adamc@31:      renameStr = #renameStr env,
adamc@31:      str = #str env}
adamc@31: 
adamc@31: fun pushSgnNamed env x sgis =
adamc@31:     let
adamc@31:         val n = !namedCounter
adamc@31:     in
adamc@31:         namedCounter := n + 1;
adamc@31:         (pushSgnNamedAs env x n sgis, n)
adamc@31:     end
adamc@31: 
adamc@31: fun lookupSgnNamed (env : env) n =
adamc@31:     case IM.find (#sgn env, n) of
adamc@31:         NONE => raise UnboundNamed n
adamc@31:       | SOME x => x
adamc@31: 
adamc@31: fun lookupSgn (env : env) x = SM.find (#renameSgn env, x)
adamc@31: 
adamc@31: fun pushStrNamedAs (env : env) x n sgis =
adamc@31:     {renameC = #renameC env,
adamc@31:      relC = #relC env,
adamc@31:      namedC = #namedC env,
adamc@31: 
adamc@31:      renameE = #renameE env,
adamc@31:      relE = #relE env,
adamc@31:      namedE = #namedE env,
adamc@31: 
adamc@31:      renameSgn = #renameSgn env,
adamc@31:      sgn = #sgn env,
adamc@31: 
adamc@31:      renameStr = SM.insert (#renameStr env, x, (n, sgis)),
adamc@31:      str = IM.insert (#str env, n, (x, sgis))}
adamc@31: 
adamc@31: fun pushStrNamed env x sgis =
adamc@31:     let
adamc@31:         val n = !namedCounter
adamc@31:     in
adamc@31:         namedCounter := n + 1;
adamc@31:         (pushStrNamedAs env x n sgis, n)
adamc@31:     end
adamc@31: 
adamc@31: fun lookupStrNamed (env : env) n =
adamc@31:     case IM.find (#str env, n) of
adamc@31:         NONE => raise UnboundNamed n
adamc@31:       | SOME x => x
adamc@31: 
adamc@31: fun lookupStr (env : env) x = SM.find (#renameStr env, x)
adamc@31: 
adamc@13: fun declBinds env (d, _) =
adamc@13:     case d of
adamc@13:         DCon (x, n, k, c) => pushCNamedAs env x n k (SOME c)
adamc@13:       | DVal (x, n, t, _) => pushENamedAs env x n t
adamc@31:       | DSgn (x, n, sgn) => pushSgnNamedAs env x n sgn
adamc@31:       | DStr (x, n, sgn, _) => pushStrNamedAs env x n sgn
adamc@48:       | DFfiStr (x, n, sgn) => pushStrNamedAs env x n sgn
adamc@31: 
adamc@31: fun sgiBinds env (sgi, _) =
adamc@31:     case sgi of
adamc@31:         SgiConAbs (x, n, k) => pushCNamedAs env x n k NONE
adamc@31:       | SgiCon (x, n, k, c) => pushCNamedAs env x n k (SOME c)
adamc@31:       | SgiVal (x, n, t) => pushENamedAs env x n t
adamc@31:       | SgiStr (x, n, sgn) => pushStrNamedAs env x n sgn
adamc@59:       | SgiSgn (x, n, sgn) => pushSgnNamedAs env x n sgn
adamc@31: 
adamc@34: fun sgnSeek f sgis =
adamc@34:     let
adamc@59:         fun seek (sgis, sgns, strs, cons) =
adamc@34:             case sgis of
adamc@34:                 [] => NONE
adamc@34:               | (sgi, _) :: sgis =>
adamc@34:                 case f sgi of
adamc@59:                     SOME v => SOME (v, (sgns, strs, cons))
adamc@34:                     | NONE =>
adamc@34:                       case sgi of
adamc@59:                           SgiConAbs (x, n, _) => seek (sgis, sgns, strs, IM.insert (cons, n, x))
adamc@59:                         | SgiCon (x, n, _, _) => seek (sgis, sgns, strs, IM.insert (cons, n, x))
adamc@59:                         | SgiVal _ => seek (sgis, sgns, strs, cons)
adamc@59:                         | SgiSgn (x, n, _) => seek (sgis, IM.insert (sgns, n, x), strs, cons)
adamc@59:                         | SgiStr (x, n, _) => seek (sgis, sgns, IM.insert (strs, n, x), cons)
adamc@34:     in
adamc@59:         seek (sgis, IM.empty, IM.empty, IM.empty)
adamc@34:     end
adamc@34: 
adamc@34: fun id x = x
adamc@34: 
adamc@34: fun unravelStr (str, _) =
adamc@34:     case str of
adamc@34:         StrVar x => (x, [])
adamc@34:       | StrProj (str, m) =>
adamc@34:         let
adamc@34:             val (x, ms) = unravelStr str
adamc@34:         in
adamc@34:             (x, ms @ [m])
adamc@34:         end
adamc@34:       | _ => raise Fail "unravelStr"
adamc@34: 
adamc@59: fun sgnS_con (str, (sgns, strs, cons)) c =
adamc@34:     case c of
adamc@34:         CModProj (m1, ms, x) =>
adamc@34:         (case IM.find (strs, m1) of
adamc@34:              NONE => c
adamc@34:            | SOME m1x =>
adamc@34:              let
adamc@34:                  val (m1, ms') = unravelStr str
adamc@34:              in
adamc@34:                  CModProj (m1, ms' @ m1x :: ms, x)
adamc@34:              end)
adamc@34:       | CNamed n =>
adamc@34:         (case IM.find (cons, n) of
adamc@34:              NONE => c
adamc@34:            | SOME nx =>
adamc@34:              let
adamc@34:                  val (m1, ms) = unravelStr str
adamc@34:              in
adamc@34:                  CModProj (m1, ms, nx)
adamc@34:              end)
adamc@34:       | _ => c
adamc@34: 
adamc@59: fun sgnS_sgn (str, (sgns, strs, cons)) sgn =
adamc@59:     case sgn of
adamc@59:         SgnProj (m1, ms, x) =>
adamc@59:         (case IM.find (strs, m1) of
adamc@59:              NONE => sgn
adamc@59:            | SOME m1x =>
adamc@59:              let
adamc@59:                  val (m1, ms') = unravelStr str
adamc@59:              in
adamc@59:                  SgnProj (m1, ms' @ m1x :: ms, x)
adamc@59:              end)
adamc@59:       | SgnVar n =>
adamc@59:         (case IM.find (sgns, n) of
adamc@59:              NONE => sgn
adamc@59:            | SOME nx =>
adamc@59:              let
adamc@59:                  val (m1, ms) = unravelStr str
adamc@59:              in
adamc@59:                  SgnProj (m1, ms, nx)
adamc@59:              end)
adamc@59:       | _ => sgn
adamc@59: 
adamc@59: fun sgnSubCon x =
adamc@34:     ElabUtil.Con.map {kind = id,
adamc@59:                       con = sgnS_con x}
adamc@34: 
adamc@59: fun sgnSubSgn x =
adamc@34:     ElabUtil.Sgn.map {kind = id,
adamc@59:                       con = sgnS_con x,
adamc@34:                       sgn_item = id,
adamc@59:                       sgn = sgnS_sgn x}
adamc@34: 
adamc@42: fun hnormSgn env (all as (sgn, loc)) =
adamc@34:     case sgn of
adamc@42:         SgnError => all
adamc@42:       | SgnVar n => hnormSgn env (#2 (lookupSgnNamed env n))
adamc@42:       | SgnConst _ => all
adamc@42:       | SgnFun _ => all
adamc@59:       | SgnProj (m, ms, x) =>
adamc@59:         let
adamc@59:             val (_, sgn) = lookupStrNamed env m
adamc@59:         in
adamc@59:             case projectSgn env {str = foldl (fn (m, str) => (StrProj (str, m), loc)) (StrVar m, loc) ms,
adamc@59:                                  sgn = sgn,
adamc@59:                                  field = x} of
adamc@59:                 NONE => raise Fail "ElabEnv.hnormSgn: projectSgn failed"
adamc@59:               | SOME sgn => sgn
adamc@59:         end
adamc@42:       | SgnWhere (sgn, x, c) =>
adamc@42:         case #1 (hnormSgn env sgn) of
adamc@42:             SgnError => (SgnError, loc)
adamc@42:           | SgnConst sgis =>
adamc@42:             let
adamc@42:                 fun traverse (pre, post) =
adamc@42:                     case post of
adamc@42:                         [] => raise Fail "ElabEnv.hnormSgn: Can't reduce 'where' [1]"
adamc@42:                       | (sgi as (SgiConAbs (x', n, k), loc)) :: rest =>
adamc@42:                         if x = x' then
adamc@42:                             List.revAppend (pre, (SgiCon (x', n, k, c), loc) :: rest)
adamc@42:                         else
adamc@42:                             traverse (sgi :: pre, rest)
adamc@42:                       | sgi :: rest => traverse (sgi :: pre, rest)
adamc@42: 
adamc@42:                 val sgis = traverse ([], sgis)
adamc@42:             in
adamc@42:                 (SgnConst sgis, loc)
adamc@42:             end
adamc@42:           | _ => raise Fail "ElabEnv.hnormSgn: Can't reduce 'where' [2]"
adamc@42: 
adamc@59: and projectSgn env {sgn, str, field} =
adamc@59:     case #1 (hnormSgn env sgn) of
adamc@59:         SgnConst sgis =>
adamc@59:         (case sgnSeek (fn SgiSgn (x, _, sgn) => if x = field then SOME sgn else NONE | _ => NONE) sgis of
adamc@59:              NONE => NONE
adamc@59:            | SOME (sgn, subs) => SOME (sgnSubSgn (str, subs) sgn))
adamc@59:       | SgnError => SOME (SgnError, ErrorMsg.dummySpan)
adamc@59:       | _ => NONE
adamc@59: 
adamc@59: fun projectStr env {sgn, str, field} =
adamc@59:     case #1 (hnormSgn env sgn) of
adamc@59:         SgnConst sgis =>
adamc@59:         (case sgnSeek (fn SgiStr (x, _, sgn) => if x = field then SOME sgn else NONE | _ => NONE) sgis of
adamc@59:              NONE => NONE
adamc@59:            | SOME (sgn, subs) => SOME (sgnSubSgn (str, subs) sgn))
adamc@59:       | SgnError => SOME (SgnError, ErrorMsg.dummySpan)
adamc@59:       | _ => NONE
adamc@59: 
adamc@42: fun projectCon env {sgn, str, field} =
adamc@42:     case #1 (hnormSgn env sgn) of
adamc@34:         SgnConst sgis =>
adamc@34:         (case sgnSeek (fn SgiConAbs (x, _, k) => if x = field then SOME (k, NONE) else NONE
adamc@34:                         | SgiCon (x, _, k, c) => if x = field then SOME (k, SOME c) else NONE
adamc@34:                         | _ => NONE) sgis of
adamc@34:              NONE => NONE
adamc@34:            | SOME ((k, co), subs) => SOME (k, Option.map (sgnSubCon (str, subs)) co))
adamc@34:       | SgnError => SOME ((KError, ErrorMsg.dummySpan), SOME (CError, ErrorMsg.dummySpan))
adamc@42:       | _ => NONE
adamc@34: 
adamc@42: fun projectVal env {sgn, str, field} =
adamc@42:     case #1 (hnormSgn env sgn) of
adamc@34:         SgnConst sgis =>
adamc@34:         (case sgnSeek (fn SgiVal (x, _, c) => if x = field then SOME c else NONE | _ => NONE) sgis of
adamc@34:              NONE => NONE
adamc@34:            | SOME (c, subs) => SOME (sgnSubCon (str, subs) c))
adamc@34:       | SgnError => SOME (CError, ErrorMsg.dummySpan)
adamc@42:       | _ => NONE
adamc@34: 
adamc@34: 
adamc@2: end