adamc@1200: (* Copyright (c) 2010, Adam Chlipala
adamc@1200:  * All rights reserved.
adamc@1200:  *
adamc@1200:  * Redistribution and use in source and binary forms, with or without
adamc@1200:  * modification, are permitted provided that the following conditions are met:
adamc@1200:  *
adamc@1200:  * - Redistributions of source code must retain the above copyright notice,
adamc@1200:  *   this list of conditions and the following disclaimer.
adamc@1200:  * - Redistributions in binary form must reproduce the above copyright notice,
adamc@1200:  *   this list of conditions and the following disclaimer in the documentation
adamc@1200:  *   and/or other materials provided with the distribution.
adamc@1200:  * - The names of contributors may not be used to endorse or promote products
adamc@1200:  *   derived from this software without specific prior written permission.
adamc@1200:  *
adamc@1200:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@1200:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@1200:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@1200:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@1200:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
adamc@1200:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@1200:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@1200:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@1200:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@1200:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@1200:  * POSSIBILITY OF SUCH DAMAGE.
adamc@1200:  *)
adamc@1200: 
adamc@1200: structure Iflow :> IFLOW = struct
adamc@1200: 
adamc@1200: open Mono
adamc@1200: 
adamc@1202: structure IM = IntBinaryMap
adamc@1202: 
adamc@1200: structure SS = BinarySetFn(struct
adamc@1200:                            type ord_key = string
adamc@1200:                            val compare = String.compare
adamc@1200:                            end)
adamc@1200: 
adamc@1200: val writers = ["htmlifyInt_w",
adamc@1200:                "htmlifyFloat_w",
adamc@1200:                "htmlifyString_w",
adamc@1200:                "htmlifyBool_w",
adamc@1200:                "htmlifyTime_w",
adamc@1200:                "attrifyInt_w",
adamc@1200:                "attrifyFloat_w",
adamc@1200:                "attrifyString_w",
adamc@1200:                "attrifyChar_w",
adamc@1200:                "urlifyInt_w",
adamc@1200:                "urlifyFloat_w",
adamc@1200:                "urlifyString_w",
adamc@1200:                "urlifyBool_w"]
adamc@1200: 
adamc@1200: val writers = SS.addList (SS.empty, writers)
adamc@1200: 
adamc@1200: type lvar = int
adamc@1200: 
adamc@1200: datatype exp =
adamc@1200:          Const of Prim.t
adamc@1200:        | Var of int
adamc@1200:        | Lvar of lvar
adamc@1200:        | Func of string * exp list
adamc@1200:        | Recd of (string * exp) list
adamc@1200:        | Proj of exp * string
adamc@1200:        | Finish
adamc@1200: 
adamc@1200: datatype reln =
adamc@1200:          Sql of string
adamc@1200:        | Eq
adamc@1200: 
adamc@1200: datatype prop =
adamc@1200:          True
adamc@1200:        | False
adamc@1200:        | Unknown
adamc@1200:        | And of prop * prop
adamc@1200:        | Or of prop * prop
adamc@1200:        | Reln of reln * exp list
adamc@1200:        | Select of int * lvar * lvar * prop * exp
adamc@1200: 
adamc@1200: local
adamc@1202:     val count = ref 1
adamc@1200: in
adamc@1200: fun newLvar () =
adamc@1200:     let
adamc@1200:         val n = !count
adamc@1200:     in
adamc@1200:         count := n + 1;
adamc@1200:         n
adamc@1200:     end
adamc@1200: end
adamc@1200: 
adamc@1200: fun subExp (v, lv) =
adamc@1200:     let
adamc@1200:         fun sub e =
adamc@1200:             case e of
adamc@1200:                 Const _ => e
adamc@1200:               | Var v' => if v' = v then Lvar lv else e
adamc@1200:               | Lvar _ => e
adamc@1200:               | Func (f, es) => Func (f, map sub es)
adamc@1200:               | Recd xes => Recd (map (fn (x, e) => (x, sub e)) xes)
adamc@1200:               | Proj (e, s) => Proj (sub e, s)
adamc@1200:               | Finish => Finish
adamc@1200:     in
adamc@1200:         sub
adamc@1200:     end
adamc@1200: 
adamc@1200: fun subProp (v, lv) =
adamc@1200:     let
adamc@1200:         fun sub p =
adamc@1200:             case p of
adamc@1200:                 True => p
adamc@1200:               | False => p
adamc@1200:               | Unknown => p
adamc@1200:               | And (p1, p2) => And (sub p1, sub p2)
adamc@1200:               | Or (p1, p2) => Or (sub p1, sub p2)
adamc@1200:               | Reln (r, es) => Reln (r, map (subExp (v, lv)) es)
adamc@1200:               | Select (v1, lv1, lv2, p, e) => Select (v1, lv1, lv2, sub p, subExp (v, lv) e)
adamc@1200:     in
adamc@1200:         sub
adamc@1200:     end
adamc@1200: 
adamc@1200: fun isKnown e =
adamc@1200:     case e of
adamc@1200:         Const _ => true
adamc@1200:       | Func (_, es) => List.all isKnown es
adamc@1200:       | Recd xes => List.all (isKnown o #2) xes
adamc@1200:       | Proj (e, _) => isKnown e
adamc@1200:       | _ => false
adamc@1200: 
adamc@1200: fun isFinish e =
adamc@1200:     case e of
adamc@1200:         Finish => true
adamc@1200:       | _ => false
adamc@1200: 
adamc@1200: fun simplify e =
adamc@1200:     case e of
adamc@1200:         Const _ => e
adamc@1200:       | Var _ => e
adamc@1200:       | Lvar _ => e
adamc@1200:       | Func (f, es) =>
adamc@1200:         let
adamc@1200:             val es = map simplify es
adamc@1200:         in
adamc@1200:             if List.exists isFinish es then
adamc@1200:                 Finish
adamc@1200:             else
adamc@1200:                 Func (f, es)
adamc@1200:         end
adamc@1200:       | Recd xes =>
adamc@1200:         let
adamc@1200:             val xes = map (fn (x, e) => (x, simplify e)) xes
adamc@1200:         in
adamc@1200:             if List.exists (isFinish o #2) xes then
adamc@1200:                 Finish
adamc@1200:             else
adamc@1200:                 Recd xes
adamc@1200:         end
adamc@1200:       | Proj (e, s) =>
adamc@1200:         (case simplify e of
adamc@1200:              Recd xes =>
adamc@1200:              getOpt (ListUtil.search (fn (x, e') => if x = s then SOME e' else NONE) xes, Recd xes)
adamc@1200:            | e' =>
adamc@1200:              if isFinish e' then
adamc@1200:                  Finish
adamc@1200:              else
adamc@1200:                  Proj (e', s))
adamc@1200:       | Finish => Finish
adamc@1200: 
adamc@1202: fun decomp fals or =
adamc@1200:     let
adamc@1200:         fun decomp p k =
adamc@1200:             case p of
adamc@1200:                 True => k []
adamc@1202:               | False => fals
adamc@1200:               | Unknown => k []
adamc@1200:               | And (p1, p2) => 
adamc@1200:                 decomp p1 (fn ps1 =>
adamc@1200:                               decomp p2 (fn ps2 =>
adamc@1200:                                             k (ps1 @ ps2)))
adamc@1200:               | Or (p1, p2) =>
adamc@1200:                 or (decomp p1 k, fn () => decomp p2 k)
adamc@1200:               | Reln x => k [x]
adamc@1200:               | Select _ => k []
adamc@1200:     in
adamc@1200:         decomp
adamc@1200:     end
adamc@1200: 
adamc@1202: val unif = ref (IM.empty : exp IM.map)
adamc@1200: 
adamc@1203: fun reset () = unif := IM.empty
adamc@1203: fun save () = !unif
adamc@1203: fun restore x = unif := x
adamc@1203: 
adamc@1202: fun lvarIn lv =
adamc@1202:     let
adamc@1202:         fun lvi e =
adamc@1202:             case e of
adamc@1202:                 Const _ => false
adamc@1202:               | Var _ => false
adamc@1202:               | Lvar lv' => lv' = lv
adamc@1202:               | Func (_, es) => List.exists lvi es
adamc@1202:               | Recd xes => List.exists (lvi o #2) xes
adamc@1202:               | Proj (e, _) => lvi e
adamc@1202:               | Finish => false
adamc@1202:     in
adamc@1202:         lvi
adamc@1202:     end
adamc@1202: 
adamc@1202: fun eq' (e1, e2) =
adamc@1202:     case (e1, e2) of
adamc@1202:         (Const p1, Const p2) => Prim.equal (p1, p2)
adamc@1202:       | (Var n1, Var n2) => n1 = n2
adamc@1202: 
adamc@1202:       | (Lvar n1, _) =>
adamc@1202:         (case IM.find (!unif, n1) of
adamc@1202:              SOME e1 => eq' (e1, e2)
adamc@1202:            | NONE =>
adamc@1202:              case e2 of
adamc@1202:                  Lvar n2 =>
adamc@1202:                  (case IM.find (!unif, n2) of
adamc@1202:                       SOME e2 => eq' (e1, e2)
adamc@1202:                     | NONE => n1 = n2
adamc@1202:                               orelse (unif := IM.insert (!unif, n1, e2);
adamc@1202:                                       true))
adamc@1202:                | _ =>
adamc@1202:                  if lvarIn n1 e2 then
adamc@1202:                      false
adamc@1202:                  else
adamc@1202:                      (unif := IM.insert (!unif, n1, e2);
adamc@1202:                       true))
adamc@1202: 
adamc@1202:       | (_, Lvar n2) =>
adamc@1202:         (case IM.find (!unif, n2) of
adamc@1202:              SOME e2 => eq' (e1, e2)
adamc@1202:            | NONE =>
adamc@1202:              if lvarIn n2 e1 then
adamc@1202:                  false
adamc@1202:              else
adamc@1202:                  (unif := IM.insert (!unif, n2, e1);
adamc@1202:                   true))
adamc@1202:                                        
adamc@1202:       | (Func (f1, es1), Func (f2, es2)) => f1 = f2 andalso ListPair.allEq eq' (es1, es2)
adamc@1202:       | (Recd xes1, Recd xes2) => ListPair.allEq (fn ((x1, e1), (x2, e2)) => x1 = x2 andalso eq' (e1, e2)) (xes1, xes2)
adamc@1202:       | (Proj (e1, s1), Proj (e2, s2)) => eq' (e1, e2) andalso s1 = s2
adamc@1202:       | (Finish, Finish) => true
adamc@1202:       | _ => false
adamc@1202: 
adamc@1202: fun eq (e1, e2) =
adamc@1202:     let
adamc@1203:         val saved = save ()
adamc@1202:     in
adamc@1202:         if eq' (simplify e1, simplify e2) then
adamc@1202:             true
adamc@1202:         else
adamc@1203:             (restore saved;
adamc@1202:              false)
adamc@1202:     end
adamc@1202: 
adamc@1202: exception Imply of prop * prop
adamc@1202: 
adamc@1202: fun rimp ((r1, es1), (r2, es2)) =
adamc@1202:     case (r1, r2) of
adamc@1202:         (Sql r1', Sql r2') =>
adamc@1202:         r1' = r2' andalso
adamc@1202:         (case (es1, es2) of
adamc@1202:              ([Recd xes1], [Recd xes2]) =>
adamc@1202:              let
adamc@1203:                  val saved = save ()
adamc@1202:              in
adamc@1202:                  if List.all (fn (f, e2) =>
adamc@1203:                                  case ListUtil.search (fn (f', e1) => if f' = f then SOME e1 else NONE) xes1 of
adamc@1203:                                      NONE => true
adamc@1203:                                    | SOME e1 => eq (e1, e2)) xes2 then
adamc@1202:                      true
adamc@1202:                  else
adamc@1203:                      (restore saved;
adamc@1202:                       false)
adamc@1202:              end
adamc@1202:            | _ => false)
adamc@1202:       | (Eq, Eq) =>
adamc@1202:         (case (es1, es2) of
adamc@1202:              ([x1, y1], [x2, y2]) =>
adamc@1202:              let
adamc@1203:                  val saved = save ()
adamc@1202:              in
adamc@1202:                  if eq (x1, x2) andalso eq (y1, y2) then
adamc@1202:                      true
adamc@1202:                  else
adamc@1203:                      (restore saved;
adamc@1202:                       (*raise Imply (Reln (Eq, es1), Reln (Eq, es2));*)
adamc@1202:                       eq (x1, y2) andalso eq (y1, x2))
adamc@1202:              end
adamc@1202:            | _ => false)
adamc@1202:       | _ => false
adamc@1202: 
adamc@1202: fun imply (p1, p2) =
adamc@1203:     (reset ();
adamc@1202:      (*raise (Imply (p1, p2));*)
adamc@1202:      decomp true (fn (e1, e2) => e1 andalso e2 ()) p1
adamc@1202:             (fn hyps =>
adamc@1202:                 decomp false (fn (e1, e2) => e1 orelse e2 ()) p2
adamc@1202:                 (fn goals =>
adamc@1202:                     let
adamc@1202:                         fun gls goals onFail =
adamc@1202:                             case goals of
adamc@1202:                                 [] => true
adamc@1202:                               | g :: goals =>
adamc@1202:                                 let
adamc@1202:                                     fun hps hyps =
adamc@1202:                                         case hyps of
adamc@1202:                                             [] => onFail ()
adamc@1202:                                           | h :: hyps =>
adamc@1202:                                             let
adamc@1203:                                                 val saved = save ()
adamc@1202:                                             in
adamc@1202:                                                 if rimp (h, g) then
adamc@1202:                                                     let
adamc@1203:                                                         val changed = IM.numItems (!unif) <> IM.numItems saved
adamc@1202:                                                     in
adamc@1203:                                                         gls goals (fn () => (restore saved;
adamc@1202:                                                                              changed andalso hps hyps))
adamc@1202:                                                     end
adamc@1202:                                                 else
adamc@1202:                                                     hps hyps
adamc@1202:                                             end
adamc@1202:                                 in
adamc@1202:                                     hps hyps
adamc@1202:                                 end
adamc@1202:                     in
adamc@1202:                         gls goals (fn () => false)
adamc@1202:                     end)))
adamc@1202: 
adamc@1200: 
adamc@1200: fun patCon pc =
adamc@1200:     case pc of
adamc@1200:         PConVar n => "C" ^ Int.toString n
adamc@1200:       | PConFfi {mod = m, datatyp = d, con = c, ...} => m ^ "." ^ d ^ "." ^ c
adamc@1200: 
adamc@1202: 
adamc@1200: 
adamc@1200: datatype chunk =
adamc@1200:          String of string
adamc@1200:        | Exp of Mono.exp
adamc@1200: 
adamc@1200: fun chunkify e =
adamc@1200:     case #1 e of
adamc@1200:         EPrim (Prim.String s) => [String s]
adamc@1200:       | EStrcat (e1, e2) => chunkify e1 @ chunkify e2
adamc@1200:       | _ => [Exp e]
adamc@1200: 
adamc@1201: type 'a parser = chunk list -> ('a * chunk list) option
adamc@1201: 
adamc@1201: fun always v chs = SOME (v, chs)
adamc@1201: 
adamc@1202: fun parse p s =
adamc@1202:     case p (chunkify s) of
adamc@1201:         SOME (v, []) => SOME v
adamc@1201:       | _ => NONE
adamc@1201: 
adamc@1201: fun const s chs =
adamc@1201:     case chs of
adamc@1201:         String s' :: chs => if String.isPrefix s s' then
adamc@1201:                                 SOME ((), if size s = size s' then
adamc@1201:                                               chs
adamc@1201:                                           else
adamc@1201:                                               String (String.extract (s', size s, NONE)) :: chs)
adamc@1201:                             else
adamc@1201:                                 NONE
adamc@1201:       | _ => NONE
adamc@1201: 
adamc@1201: fun follow p1 p2 chs =
adamc@1201:     case p1 chs of
adamc@1201:         NONE => NONE
adamc@1201:       | SOME (v1, chs) =>
adamc@1201:         case p2 chs of
adamc@1201:             NONE => NONE
adamc@1201:           | SOME (v2, chs) => SOME ((v1, v2), chs)
adamc@1201: 
adamc@1201: fun wrap p f chs =
adamc@1201:     case p chs of
adamc@1201:         NONE => NONE
adamc@1201:       | SOME (v, chs) => SOME (f v, chs)
adamc@1201: 
adamc@1201: fun alt p1 p2 chs =
adamc@1201:     case p1 chs of
adamc@1201:         NONE => p2 chs
adamc@1201:       | v => v
adamc@1201: 
adamc@1201: fun skip cp chs =
adamc@1201:     case chs of
adamc@1201:         String "" :: chs => skip cp chs
adamc@1201:       | String s :: chs' => if cp (String.sub (s, 0)) then
adamc@1201:                                 skip cp (String (String.extract (s, 1, NONE)) :: chs')
adamc@1201:                             else
adamc@1201:                                 SOME ((), chs)
adamc@1201:       | _ => SOME ((), chs)
adamc@1201: 
adamc@1201: fun keep cp chs =
adamc@1201:     case chs of
adamc@1201:         String "" :: chs => keep cp chs
adamc@1201:       | String s :: chs' =>
adamc@1201:         let
adamc@1201:             val (befor, after) = Substring.splitl cp (Substring.full s)
adamc@1201:         in
adamc@1201:             if Substring.isEmpty befor then
adamc@1201:                 NONE
adamc@1201:             else
adamc@1201:                 SOME (Substring.string befor,
adamc@1201:                       if Substring.isEmpty after then
adamc@1201:                           chs'
adamc@1201:                       else
adamc@1201:                           String (Substring.string after) :: chs')
adamc@1201:         end
adamc@1201:       | _ => NONE
adamc@1201: 
adamc@1201: fun ws p = wrap (follow p (skip (fn ch => ch = #" "))) #1
adamc@1201: 
adamc@1201: fun list p chs =
adamc@1201:     (alt (wrap (follow p (follow (ws (const ",")) (list p)))
adamc@1201:                (fn (v, ((), ls)) => v :: ls))
adamc@1201:          (alt (wrap (ws p) (fn v => [v]))
adamc@1201:               (always []))) chs
adamc@1201: 
adamc@1201: val ident = keep (fn ch => Char.isAlphaNum ch orelse ch = #"_")
adamc@1201: 
adamc@1201: val t_ident = wrap ident (fn s => if String.isPrefix "T_" s then
adamc@1201:                                       String.extract (s, 2, NONE)
adamc@1201:                                   else
adamc@1201:                                       raise Fail "Iflow: Bad table variable")
adamc@1201: val uw_ident = wrap ident (fn s => if String.isPrefix "uw_" s then
adamc@1201:                                        String.extract (s, 3, NONE)
adamc@1201:                                    else
adamc@1201:                                        raise Fail "Iflow: Bad uw_* variable")
adamc@1201: 
adamc@1201: val sitem = wrap (follow t_ident
adamc@1201:                          (follow (const ".")
adamc@1201:                                  uw_ident))
adamc@1201:                  (fn (t, ((), f)) => (t, f))
adamc@1201: 
adamc@1201: val select = wrap (follow (const "SELECT ") (list sitem))
adamc@1201:                   (fn ((), ls) => ls)
adamc@1201: 
adamc@1201: val fitem = wrap (follow uw_ident
adamc@1201:                          (follow (const " AS ")
adamc@1201:                                  t_ident))
adamc@1201:                  (fn (t, ((), f)) => (t, f))
adamc@1201: 
adamc@1201: val from = wrap (follow (const "FROM ") (list fitem))
adamc@1201:                 (fn ((), ls) => ls)
adamc@1201: 
adamc@1201: val query = wrap (follow select from)
adamc@1201:             (fn (fs, ts) => {Select = fs, From = ts})
adamc@1201: 
adamc@1202: fun queryProp rv oe e =
adamc@1202:     case parse query e of
adamc@1201:         NONE => Unknown
adamc@1201:       | SOME r =>
adamc@1202:         let
adamc@1202:             val p =
adamc@1202:                 foldl (fn ((t, v), p) =>
adamc@1202:                           And (p,
adamc@1202:                                Reln (Sql t,
adamc@1202:                                      [Recd (foldl (fn ((v', f), fs) =>
adamc@1202:                                                       if v' = v then
adamc@1202:                                                           (f, Proj (Proj (Lvar rv, v), f)) :: fs
adamc@1202:                                                       else
adamc@1202:                                                           fs) [] (#Select r))])))
adamc@1202:                       True (#From r)
adamc@1202:         in
adamc@1202:             case oe of
adamc@1202:                 NONE => p
adamc@1202:               | SOME oe =>
adamc@1202:                 And (p,
adamc@1202:                      foldl (fn ((v, f), p) =>
adamc@1202:                                Or (p,
adamc@1202:                                    Reln (Eq, [oe, Proj (Proj (Lvar rv, v), f)])))
adamc@1202:                            False (#Select r))
adamc@1202:         end
adamc@1200: 
adamc@1202: fun evalExp env (e as (_, loc), st as (nv, p, sent)) =
adamc@1200:     let
adamc@1200:         fun default () =
adamc@1200:             (Var nv, (nv+1, p, sent))
adamc@1200: 
adamc@1200:         fun addSent (p, e, sent) =
adamc@1200:             if isKnown e then
adamc@1200:                 sent
adamc@1200:             else
adamc@1202:                 (loc, e, p) :: sent
adamc@1200:     in
adamc@1200:         case #1 e of
adamc@1200:             EPrim p => (Const p, st)
adamc@1200:           | ERel n => (List.nth (env, n), st)
adamc@1200:           | ENamed _ => default ()
adamc@1200:           | ECon (_, pc, NONE) => (Func (patCon pc, []), st)
adamc@1200:           | ECon (_, pc, SOME e) =>
adamc@1200:             let
adamc@1200:                 val (e, st) = evalExp env (e, st)
adamc@1200:             in
adamc@1200:                 (Func (patCon pc, [e]), st)
adamc@1200:             end
adamc@1200:           | ENone _ => (Func ("None", []), st)
adamc@1200:           | ESome (_, e) =>
adamc@1200:             let
adamc@1200:                 val (e, st) = evalExp env (e, st)
adamc@1200:             in
adamc@1200:                 (Func ("Some", [e]), st)
adamc@1200:             end
adamc@1200:           | EFfi _ => default ()
adamc@1200:           | EFfiApp (m, s, es) =>
adamc@1200:             if m = "Basis" andalso SS.member (writers, s) then
adamc@1200:                 let
adamc@1200:                     val (es, st) = ListUtil.foldlMap (evalExp env) st es
adamc@1200:                 in
adamc@1200:                     (Func ("unit", []), (#1 st, p, foldl (fn (e, sent) => addSent (#2 st, e, sent)) sent es))
adamc@1200:                 end
adamc@1200:             else if Settings.isEffectful (m, s) andalso not (Settings.isBenignEffectful (m, s)) then
adamc@1200:                 default ()
adamc@1200:             else
adamc@1200:                 let
adamc@1200:                     val (es, st) = ListUtil.foldlMap (evalExp env) st es
adamc@1200:                 in
adamc@1200:                     (Func (m ^ "." ^ s, es), st)
adamc@1200:                 end
adamc@1200:           | EApp _ => default ()
adamc@1200:           | EAbs _ => default ()
adamc@1200:           | EUnop (s, e1) =>
adamc@1200:             let
adamc@1200:                 val (e1, st) = evalExp env (e1, st)
adamc@1200:             in
adamc@1200:                 (Func (s, [e1]), st)
adamc@1200:             end
adamc@1200:           | EBinop (s, e1, e2) =>
adamc@1200:             let
adamc@1200:                 val (e1, st) = evalExp env (e1, st)
adamc@1200:                 val (e2, st) = evalExp env (e2, st)
adamc@1200:             in
adamc@1200:                 (Func (s, [e1, e2]), st)
adamc@1200:             end
adamc@1200:           | ERecord xets =>
adamc@1200:             let
adamc@1200:                 val (xes, st) = ListUtil.foldlMap (fn ((x, e, _), st) =>
adamc@1200:                                                       let
adamc@1200:                                                           val (e, st) = evalExp env (e, st)
adamc@1200:                                                       in
adamc@1200:                                                           ((x, e), st)
adamc@1200:                                                       end) st xets
adamc@1200:             in
adamc@1200:                 (Recd xes, st)
adamc@1200:             end
adamc@1200:           | EField (e, s) =>
adamc@1200:             let
adamc@1200:                 val (e, st) = evalExp env (e, st)
adamc@1200:             in
adamc@1200:                 (Proj (e, s), st)
adamc@1200:             end
adamc@1200:           | ECase _ => default ()
adamc@1200:           | EStrcat (e1, e2) =>
adamc@1200:             let
adamc@1200:                 val (e1, st) = evalExp env (e1, st)
adamc@1200:                 val (e2, st) = evalExp env (e2, st)
adamc@1200:             in
adamc@1200:                 (Func ("cat", [e1, e2]), st)
adamc@1200:             end
adamc@1200:           | EError _ => (Finish, st)
adamc@1200:           | EReturnBlob {blob = b, mimeType = m, ...} =>
adamc@1200:             let
adamc@1200:                 val (b, st) = evalExp env (b, st)
adamc@1200:                 val (m, st) = evalExp env (m, st)
adamc@1200:             in
adamc@1200:                 (Finish, (#1 st, p, addSent (#2 st, b, addSent (#2 st, m, sent))))
adamc@1200:             end
adamc@1200:           | ERedirect (e, _) =>
adamc@1200:             let
adamc@1200:                 val (e, st) = evalExp env (e, st)
adamc@1200:             in
adamc@1200:                 (Finish, (#1 st, p, addSent (#2 st, e, sent)))
adamc@1200:             end
adamc@1200:           | EWrite e =>
adamc@1200:             let
adamc@1200:                 val (e, st) = evalExp env (e, st)
adamc@1200:             in
adamc@1200:                 (Func ("unit", []), (#1 st, p, addSent (#2 st, e, sent)))
adamc@1200:             end
adamc@1200:           | ESeq (e1, e2) =>
adamc@1200:             let
adamc@1200:                 val (_, st) = evalExp env (e1, st)
adamc@1200:             in
adamc@1200:                 evalExp env (e2, st)
adamc@1200:             end
adamc@1200:           | ELet (_, _, e1, e2) =>
adamc@1200:             let
adamc@1200:                 val (e1, st) = evalExp env (e1, st)
adamc@1200:             in
adamc@1200:                 evalExp (e1 :: env) (e2, st)
adamc@1200:             end
adamc@1200:           | EClosure (n, es) =>
adamc@1200:             let
adamc@1200:                 val (es, st) = ListUtil.foldlMap (evalExp env) st es
adamc@1200:             in
adamc@1200:                 (Func ("Cl" ^ Int.toString n, es), st)
adamc@1200:             end
adamc@1200: 
adamc@1200:           | EQuery {query = q, body = b, initial = i, ...} =>
adamc@1200:             let
adamc@1200:                 val (_, st) = evalExp env (q, st)
adamc@1200:                 val (i, st) = evalExp env (i, st)
adamc@1200: 
adamc@1200:                 val r = #1 st
adamc@1200:                 val acc = #1 st + 1
adamc@1200:                 val st' = (#1 st + 2, #2 st, #3 st)
adamc@1200: 
adamc@1200:                 val (b, st') = evalExp (Var acc :: Var r :: env) (b, st')
adamc@1200: 
adamc@1200:                 val r' = newLvar ()
adamc@1200:                 val acc' = newLvar ()
adamc@1202:                 val qp = queryProp r' NONE q
adamc@1200: 
adamc@1200:                 val doSubExp = subExp (r, r') o subExp (acc, acc')
adamc@1200:                 val doSubProp = subProp (r, r') o subProp (acc, acc')
adamc@1200: 
adamc@1200:                 val p = doSubProp (#2 st')
adamc@1200:                 val p = And (p, qp)
adamc@1200:                 val p = Select (r, r', acc', p, doSubExp b)
adamc@1200:             in
adamc@1202:                 (Var r, (#1 st + 1, And (#2 st, p), map (fn (loc, e, p) => (loc,
adamc@1202:                                                                             doSubExp e,
adamc@1202:                                                                             And (qp, doSubProp p))) (#3 st')))
adamc@1200:             end
adamc@1200:           | EDml _ => default ()
adamc@1200:           | ENextval _ => default ()
adamc@1200:           | ESetval _ => default ()
adamc@1200: 
adamc@1200:           | EUnurlify _ => default ()
adamc@1200:           | EJavaScript _ => default ()
adamc@1200:           | ESignalReturn _ => default ()
adamc@1200:           | ESignalBind _ => default ()
adamc@1200:           | ESignalSource _ => default ()
adamc@1200:           | EServerCall _ => default ()
adamc@1200:           | ERecv _ => default ()
adamc@1200:           | ESleep _ => default ()
adamc@1200:           | ESpawn _ => default ()
adamc@1200:     end
adamc@1200: 
adamc@1200: fun check file =
adamc@1200:     let
adamc@1202:         fun decl ((d, _), (vals, pols)) =
adamc@1200:             case d of
adamc@1200:                 DVal (x, _, _, e, _) =>
adamc@1200:                 let
adamc@1200:                     fun deAbs (e, env, nv) =
adamc@1200:                         case #1 e of
adamc@1200:                             EAbs (_, _, _, e) => deAbs (e, Var nv :: env, nv + 1)
adamc@1200:                           | _ => (e, env, nv)
adamc@1200: 
adamc@1202:                     val (e, env, nv) = deAbs (e, [], 1)
adamc@1200: 
adamc@1200:                     val (e, (_, p, sent)) = evalExp env (e, (nv, True, []))
adamc@1200:                 in
adamc@1202:                     ((x, e, p, sent) :: vals, pols)
adamc@1200:                 end
adamc@1202: 
adamc@1202:               | DPolicy (PolQuery e) => (vals, queryProp 0 (SOME (Var 0)) e :: pols)
adamc@1202: 
adamc@1202:               | _ => (vals, pols)
adamc@1202: 
adamc@1203:         val () = reset ()
adamc@1202: 
adamc@1202:         val (vals, pols) = foldl decl ([], []) file
adamc@1200:     in
adamc@1202:         app (fn (name, _, _, sent) =>
adamc@1202:                 app (fn (loc, e, p) =>
adamc@1202:                         let
adamc@1202:                             val p = And (p, Reln (Eq, [Var 0, e]))
adamc@1202:                         in
adamc@1202:                             if List.exists (fn pol => imply (p, pol)) pols then
adamc@1202:                                 ()
adamc@1202:                             else
adamc@1202:                                 ErrorMsg.errorAt loc "The information flow policy may be violated here."
adamc@1202:                         end) sent) vals
adamc@1200:     end
adamc@1200: 
adamc@1200: end