adamc@38: (* Copyright (c) 2008, Adam Chlipala
adamc@38:  * All rights reserved.
adamc@38:  *
adamc@38:  * Redistribution and use in source and binary forms, with or without
adamc@38:  * modification, are permitted provided that the following conditions are met:
adamc@38:  *
adamc@38:  * - Redistributions of source code must retain the above copyright notice,
adamc@38:  *   this list of conditions and the following disclaimer.
adamc@38:  * - Redistributions in binary form must reproduce the above copyright notice,
adamc@38:  *   this list of conditions and the following disclaimer in the documentation
adamc@38:  *   and/or other materials provided with the distribution.
adamc@38:  * - The names of contributors may not be used to endorse or promote products
adamc@38:  *   derived from this software without specific prior written permission.
adamc@38:  *
adamc@38:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@38:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@38:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@38:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@38:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
adamc@38:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@38:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@38:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@38:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@38:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@38:  * POSSIBILITY OF SUCH DAMAGE.
adamc@38:  *)
adamc@38: 
adamc@38: structure ExplEnv :> EXPL_ENV = struct
adamc@38: 
adamc@38: open Expl
adamc@38: 
adamc@38: structure U = ExplUtil
adamc@38: 
adamc@38: structure IM = IntBinaryMap
adamc@38: structure SM = BinaryMapFn(struct
adamc@38:                            type ord_key = string
adamc@38:                            val compare = String.compare
adamc@38:                            end)
adamc@38: 
adamc@38: exception UnboundRel of int
adamc@38: exception UnboundNamed of int
adamc@38: 
adamc@38: 
adamc@38: (* AST utility functions *)
adamc@38: 
adamc@38: exception SynUnif
adamc@38: 
adamc@38: val liftConInCon =
adamc@38:     U.Con.mapB {kind = fn k => k,
adamc@38:                 con = fn bound => fn c =>
adamc@38:                                      case c of
adamc@38:                                          CRel xn =>
adamc@38:                                          if xn < bound then
adamc@38:                                              c
adamc@38:                                          else
adamc@38:                                              CRel (xn + 1)
adamc@38:                                        (*| CUnif _ => raise SynUnif*)
adamc@38:                                        | _ => c,
adamc@38:                 bind = fn (bound, U.Con.Rel _) => bound + 1
adamc@38:                         | (bound, _) => bound}
adamc@38: 
adamc@38: val lift = liftConInCon 0
adamc@38: 
adamc@38: 
adamc@38: (* Back to environments *)
adamc@38: 
adamc@38: datatype 'a var' =
adamc@38:          Rel' of int * 'a
adamc@38:        | Named' of int * 'a
adamc@38: 
adamc@38: datatype 'a var =
adamc@38:          NotBound
adamc@38:        | Rel of int * 'a
adamc@38:        | Named of int * 'a
adamc@38: 
adamc@38: type env = {
adamc@38:      renameC : kind var' SM.map,
adamc@38:      relC : (string * kind) list,
adamc@38:      namedC : (string * kind * con option) IM.map,
adamc@38: 
adamc@38:      renameE : con var' SM.map,
adamc@38:      relE : (string * con) list,
adamc@38:      namedE : (string * con) IM.map,
adamc@38: 
adamc@38:      renameSgn : (int * sgn) SM.map,
adamc@38:      sgn : (string * sgn) IM.map,
adamc@38: 
adamc@38:      renameStr : (int * sgn) SM.map,
adamc@38:      str : (string * sgn) IM.map
adamc@38: }
adamc@38: 
adamc@38: val namedCounter = ref 0
adamc@38: 
adamc@38: val empty = {
adamc@38:     renameC = SM.empty,
adamc@38:     relC = [],
adamc@38:     namedC = IM.empty,
adamc@38: 
adamc@38:     renameE = SM.empty,
adamc@38:     relE = [],
adamc@38:     namedE = IM.empty,
adamc@38: 
adamc@38:     renameSgn = SM.empty,
adamc@38:     sgn = IM.empty,
adamc@38: 
adamc@38:     renameStr = SM.empty,
adamc@38:     str = IM.empty
adamc@38: }
adamc@38: 
adamc@38: fun pushCRel (env : env) x k =
adamc@38:     let
adamc@38:         val renameC = SM.map (fn Rel' (n, k) => Rel' (n+1, k)
adamc@38:                                | x => x) (#renameC env)
adamc@38:     in
adamc@38:         {renameC = SM.insert (renameC, x, Rel' (0, k)),
adamc@38:          relC = (x, k) :: #relC env,
adamc@38:          namedC = IM.map (fn (x, k, co) => (x, k, Option.map lift co)) (#namedC env),
adamc@38: 
adamc@38:          renameE = #renameE env,
adamc@38:          relE = map (fn (x, c) => (x, lift c)) (#relE env),
adamc@38:          namedE = IM.map (fn (x, c) => (x, lift c)) (#namedE env),
adamc@38: 
adamc@38:          renameSgn = #renameSgn env,
adamc@38:          sgn = #sgn env,
adamc@38: 
adamc@38:          renameStr = #renameStr env,
adamc@38:          str = #str env
adamc@38:         }
adamc@38:     end
adamc@38: 
adamc@38: fun lookupCRel (env : env) n =
adamc@38:     (List.nth (#relC env, n))
adamc@38:     handle Subscript => raise UnboundRel n
adamc@38: 
adamc@38: fun pushCNamed (env : env) x n k co =
adamc@38:     {renameC = SM.insert (#renameC env, x, Named' (n, k)),
adamc@38:      relC = #relC env,
adamc@38:      namedC = IM.insert (#namedC env, n, (x, k, co)),
adamc@38: 
adamc@38:      renameE = #renameE env,
adamc@38:      relE = #relE env,
adamc@38:      namedE = #namedE env,
adamc@38: 
adamc@38:      renameSgn = #renameSgn env,
adamc@38:      sgn = #sgn env,
adamc@38:      
adamc@38:      renameStr = #renameStr env,
adamc@38:      str = #str env}
adamc@38: 
adamc@38: fun lookupCNamed (env : env) n =
adamc@38:     case IM.find (#namedC env, n) of
adamc@38:         NONE => raise UnboundNamed n
adamc@38:       | SOME x => x
adamc@38: 
adamc@38: fun pushERel (env : env) x t =
adamc@38:     let
adamc@38:         val renameE = SM.map (fn Rel' (n, t) => Rel' (n+1, t)
adamc@38:                                | x => x) (#renameE env)
adamc@38:     in
adamc@38:         {renameC = #renameC env,
adamc@38:          relC = #relC env,
adamc@38:          namedC = #namedC env,
adamc@38: 
adamc@38:          renameE = SM.insert (renameE, x, Rel' (0, t)),
adamc@38:          relE = (x, t) :: #relE env,
adamc@38:          namedE = #namedE env,
adamc@38: 
adamc@38:          renameSgn = #renameSgn env,
adamc@38:          sgn = #sgn env,
adamc@38: 
adamc@38:          renameStr = #renameStr env,
adamc@38:          str = #str env}
adamc@38:     end
adamc@38: 
adamc@38: fun lookupERel (env : env) n =
adamc@38:     (List.nth (#relE env, n))
adamc@38:     handle Subscript => raise UnboundRel n
adamc@38: 
adamc@38: fun pushENamed (env : env) x n t =
adamc@38:     {renameC = #renameC env,
adamc@38:      relC = #relC env,
adamc@38:      namedC = #namedC env,
adamc@38: 
adamc@38:      renameE = SM.insert (#renameE env, x, Named' (n, t)),
adamc@38:      relE = #relE env,
adamc@38:      namedE = IM.insert (#namedE env, n, (x, t)),
adamc@38: 
adamc@38:      renameSgn = #renameSgn env,
adamc@38:      sgn = #sgn env,
adamc@38:      
adamc@38:      renameStr = #renameStr env,
adamc@38:      str = #str env}
adamc@38: 
adamc@38: fun lookupENamed (env : env) n =
adamc@38:     case IM.find (#namedE env, n) of
adamc@38:         NONE => raise UnboundNamed n
adamc@38:       | SOME x => x
adamc@38: 
adamc@38: fun pushSgnNamed (env : env) x n sgis =
adamc@38:     {renameC = #renameC env,
adamc@38:      relC = #relC env,
adamc@38:      namedC = #namedC env,
adamc@38: 
adamc@38:      renameE = #renameE env,
adamc@38:      relE = #relE env,
adamc@38:      namedE = #namedE env,
adamc@38: 
adamc@38:      renameSgn = SM.insert (#renameSgn env, x, (n, sgis)),
adamc@38:      sgn = IM.insert (#sgn env, n, (x, sgis)),
adamc@38:      
adamc@38:      renameStr = #renameStr env,
adamc@38:      str = #str env}
adamc@38: 
adamc@38: fun lookupSgnNamed (env : env) n =
adamc@38:     case IM.find (#sgn env, n) of
adamc@38:         NONE => raise UnboundNamed n
adamc@38:       | SOME x => x
adamc@38: 
adamc@38: fun pushStrNamed (env : env) x n sgis =
adamc@38:     {renameC = #renameC env,
adamc@38:      relC = #relC env,
adamc@38:      namedC = #namedC env,
adamc@38: 
adamc@38:      renameE = #renameE env,
adamc@38:      relE = #relE env,
adamc@38:      namedE = #namedE env,
adamc@38: 
adamc@38:      renameSgn = #renameSgn env,
adamc@38:      sgn = #sgn env,
adamc@38: 
adamc@38:      renameStr = SM.insert (#renameStr env, x, (n, sgis)),
adamc@38:      str = IM.insert (#str env, n, (x, sgis))}
adamc@38: 
adamc@38: fun lookupStrNamed (env : env) n =
adamc@38:     case IM.find (#str env, n) of
adamc@38:         NONE => raise UnboundNamed n
adamc@38:       | SOME x => x
adamc@38: 
adamc@162: fun declBinds env (d, loc) =
adamc@38:     case d of
adamc@38:         DCon (x, n, k, c) => pushCNamed env x n k (SOME c)
adamc@191:       | DDatatype (x, n, xs, xncs) =>
adamc@162:         let
adamc@162:             val env = pushCNamed env x n (KType, loc) NONE
adamc@162:         in
adamc@191:             foldl (fn ((x', n', to), env) =>
adamc@191:                       let
adamc@191:                           val t =
adamc@191:                               case to of
adamc@191:                                   NONE => (CNamed n, loc)
adamc@191:                                 | SOME t => (TFun (t, (CNamed n, loc)), loc)
adamc@191:                           val k = (KType, loc)
adamc@191:                           val t = foldr (fn (x, t) => (TCFun (x, k, t), loc)) t xs
adamc@191:                       in
adamc@191:                           pushENamed env x' n' t
adamc@191:                       end)
adamc@191:                   env xncs
adamc@162:         end
adamc@191:       | DDatatypeImp (x, n, m, ms, x', xs, xncs) =>
adamc@162:         let
adamc@162:             val t = (CModProj (m, ms, x'), loc)
adamc@162:             val env = pushCNamed env x n (KType, loc) (SOME t)
adamc@162: 
adamc@162:             val t = (CNamed n, loc)
adamc@162:         in
adamc@191:             foldl (fn ((x', n', to), env) =>
adamc@191:                       let
adamc@191:                           val t =
adamc@191:                               case to of
adamc@191:                                   NONE => (CNamed n, loc)
adamc@191:                                 | SOME t => (TFun (t, (CNamed n, loc)), loc)
adamc@191:                           val k = (KType, loc)
adamc@191:                           val t = foldr (fn (x, t) => (TCFun (x, k, t), loc)) t xs
adamc@191:                       in
adamc@191:                           pushENamed env x' n' t
adamc@191:                       end)
adamc@191:                   env xncs
adamc@162:         end
adamc@38:       | DVal (x, n, t, _) => pushENamed env x n t
adamc@124:       | DValRec vis => foldl (fn ((x, n, t, _), env) => pushENamed env x n t) env vis
adamc@38:       | DSgn (x, n, sgn) => pushSgnNamed env x n sgn
adamc@38:       | DStr (x, n, sgn, _) => pushStrNamed env x n sgn
adamc@48:       | DFfiStr (x, n, sgn) => pushStrNamed env x n sgn
adamc@109:       | DExport _ => env
adamc@38: 
adamc@162: fun sgiBinds env (sgi, loc) =
adamc@38:     case sgi of
adamc@38:         SgiConAbs (x, n, k) => pushCNamed env x n k NONE
adamc@38:       | SgiCon (x, n, k, c) => pushCNamed env x n k (SOME c)
adamc@191:       | SgiDatatype (x, n, xs, xncs) =>
adamc@162:         let
adamc@162:             val env = pushCNamed env x n (KType, loc) NONE
adamc@162:         in
adamc@191:             foldl (fn ((x', n', to), env) =>
adamc@191:                       let
adamc@191:                           val t =
adamc@191:                               case to of
adamc@191:                                   NONE => (CNamed n, loc)
adamc@191:                                 | SOME t => (TFun (t, (CNamed n, loc)), loc)
adamc@191:                           val k = (KType, loc)
adamc@191:                           val t = foldr (fn (x, t) => (TCFun (x, k, t), loc)) t xs
adamc@191:                       in
adamc@191:                           pushENamed env x' n' t
adamc@191:                       end)
adamc@191:                   env xncs
adamc@162:         end
adamc@191:       | SgiDatatypeImp (x, n, m1, ms, x', xs, xncs) =>
adamc@162:         let
adamc@191:             val t = (CModProj (m1, ms, x'), loc)
adamc@191:             val env = pushCNamed env x n (KType, loc) (SOME t)
adamc@191: 
adamc@191:             val t = (CNamed n, loc)
adamc@162:         in
adamc@191:             foldl (fn ((x', n', to), env) =>
adamc@191:                       let
adamc@191:                           val t =
adamc@191:                               case to of
adamc@191:                                   NONE => (CNamed n, loc)
adamc@191:                                 | SOME t => (TFun (t, (CNamed n, loc)), loc)
adamc@191:                           val k = (KType, loc)
adamc@191:                           val t = foldr (fn (x, t) => (TCFun (x, k, t), loc)) t xs
adamc@191:                       in
adamc@191:                           pushENamed env x' n' t
adamc@191:                       end)
adamc@191:                   env xncs
adamc@162:         end
adamc@38:       | SgiVal (x, n, t) => pushENamed env x n t
adamc@64:       | SgiSgn (x, n, sgn) => pushSgnNamed env x n sgn
adamc@38:       | SgiStr (x, n, sgn) => pushStrNamed env x n sgn
adamc@38: 
adamc@38: end