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|
(* 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 Elaborate :> ELABORATE = struct
structure P = Prim
structure L = Source
structure L' = Elab
structure E = ElabEnv
structure U = ElabUtil
open Print
open ElabPrint
structure SS = BinarySetFn(struct
type ord_key = string
val compare = String.compare
end)
fun elabExplicitness e =
case e of
L.Explicit => L'.Explicit
| L.Implicit => L'.Implicit
fun occursKind r =
U.Kind.exists (fn L'.KUnif (_, _, r') => r = r'
| _ => false)
datatype kunify_error =
KOccursCheckFailed of L'.kind * L'.kind
| KIncompatible of L'.kind * L'.kind
exception KUnify' of kunify_error
fun kunifyError err =
case err of
KOccursCheckFailed (k1, k2) =>
eprefaces "Kind occurs check failed"
[("Kind 1", p_kind k1),
("Kind 2", p_kind k2)]
| KIncompatible (k1, k2) =>
eprefaces "Incompatible kinds"
[("Kind 1", p_kind k1),
("Kind 2", p_kind k2)]
fun unifyKinds' (k1All as (k1, _)) (k2All as (k2, _)) =
let
fun err f = raise KUnify' (f (k1All, k2All))
in
case (k1, k2) of
(L'.KType, L'.KType) => ()
| (L'.KArrow (d1, r1), L'.KArrow (d2, r2)) =>
(unifyKinds' d1 d2;
unifyKinds' r1 r2)
| (L'.KName, L'.KName) => ()
| (L'.KRecord k1, L'.KRecord k2) => unifyKinds' k1 k2
| (L'.KError, _) => ()
| (_, L'.KError) => ()
| (L'.KUnif (_, _, ref (SOME k1All)), _) => unifyKinds' k1All k2All
| (_, L'.KUnif (_, _, ref (SOME k2All))) => unifyKinds' k1All k2All
| (L'.KUnif (_, _, r1), L'.KUnif (_, _, r2)) =>
if r1 = r2 then
()
else
r1 := SOME k2All
| (L'.KUnif (_, _, r), _) =>
if occursKind r k2All then
err KOccursCheckFailed
else
r := SOME k2All
| (_, L'.KUnif (_, _, r)) =>
if occursKind r k1All then
err KOccursCheckFailed
else
r := SOME k1All
| _ => err KIncompatible
end
exception KUnify of L'.kind * L'.kind * kunify_error
fun unifyKinds k1 k2 =
unifyKinds' k1 k2
handle KUnify' err => raise KUnify (k1, k2, err)
datatype con_error =
UnboundCon of ErrorMsg.span * string
| UnboundStrInCon of ErrorMsg.span * string
| WrongKind of L'.con * L'.kind * L'.kind * kunify_error
| DuplicateField of ErrorMsg.span * string
fun conError env err =
case err of
UnboundCon (loc, s) =>
ErrorMsg.errorAt loc ("Unbound constructor variable " ^ s)
| UnboundStrInCon (loc, s) =>
ErrorMsg.errorAt loc ("Unbound structure " ^ s)
| WrongKind (c, k1, k2, kerr) =>
(ErrorMsg.errorAt (#2 c) "Wrong kind";
eprefaces' [("Constructor", p_con env c),
("Have kind", p_kind k1),
("Need kind", p_kind k2)];
kunifyError kerr)
| DuplicateField (loc, s) =>
ErrorMsg.errorAt loc ("Duplicate record field " ^ s)
fun checkKind env c k1 k2 =
unifyKinds k1 k2
handle KUnify (k1, k2, err) =>
conError env (WrongKind (c, k1, k2, err))
val dummy = ErrorMsg.dummySpan
val ktype = (L'.KType, dummy)
val kname = (L'.KName, dummy)
val ktype_record = (L'.KRecord ktype, dummy)
val cerror = (L'.CError, dummy)
val kerror = (L'.KError, dummy)
val eerror = (L'.EError, dummy)
val sgnerror = (L'.SgnError, dummy)
val strerror = (L'.StrError, dummy)
val int = ref cerror
val float = ref cerror
val string = ref cerror
local
val count = ref 0
in
fun resetKunif () = count := 0
fun kunif loc =
let
val n = !count
val s = if n <= 26 then
str (chr (ord #"A" + n))
else
"U" ^ Int.toString (n - 26)
in
count := n + 1;
(L'.KUnif (loc, s, ref NONE), dummy)
end
end
local
val count = ref 0
in
fun resetCunif () = count := 0
fun cunif (loc, k) =
let
val n = !count
val s = if n <= 26 then
str (chr (ord #"A" + n))
else
"U" ^ Int.toString (n - 26)
in
count := n + 1;
(L'.CUnif (loc, k, s, ref NONE), dummy)
end
end
fun elabKind (k, loc) =
case k of
L.KType => (L'.KType, loc)
| L.KArrow (k1, k2) => (L'.KArrow (elabKind k1, elabKind k2), loc)
| L.KName => (L'.KName, loc)
| L.KRecord k => (L'.KRecord (elabKind k), loc)
| L.KWild => kunif loc
fun foldKind (dom, ran, loc)=
(L'.KArrow ((L'.KArrow ((L'.KName, loc),
(L'.KArrow (dom,
(L'.KArrow (ran, ran), loc)), loc)), loc),
(L'.KArrow (ran,
(L'.KArrow ((L'.KRecord dom, loc),
ran), loc)), loc)), loc)
fun elabCon env (c, loc) =
case c of
L.CAnnot (c, k) =>
let
val k' = elabKind k
val (c', ck) = elabCon env c
in
checkKind env c' ck k';
(c', k')
end
| L.TFun (t1, t2) =>
let
val (t1', k1) = elabCon env t1
val (t2', k2) = elabCon env t2
in
checkKind env t1' k1 ktype;
checkKind env t2' k2 ktype;
((L'.TFun (t1', t2'), loc), ktype)
end
| L.TCFun (e, x, k, t) =>
let
val e' = elabExplicitness e
val k' = elabKind k
val env' = E.pushCRel env x k'
val (t', tk) = elabCon env' t
in
checkKind env t' tk ktype;
((L'.TCFun (e', x, k', t'), loc), ktype)
end
| L.TRecord c =>
let
val (c', ck) = elabCon env c
val k = (L'.KRecord ktype, loc)
in
checkKind env c' ck k;
((L'.TRecord c', loc), ktype)
end
| L.CVar ([], s) =>
(case E.lookupC env s of
E.NotBound =>
(conError env (UnboundCon (loc, s));
(cerror, kerror))
| E.Rel (n, k) =>
((L'.CRel n, loc), k)
| E.Named (n, k) =>
((L'.CNamed n, loc), k))
| L.CVar (m1 :: ms, s) =>
(case E.lookupStr env m1 of
NONE => (conError env (UnboundStrInCon (loc, m1));
(cerror, kerror))
| SOME (n, sgn) =>
let
val (str, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {sgn = sgn, str = str, field = m} of
NONE => (conError env (UnboundStrInCon (loc, m));
(strerror, sgnerror))
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
val k = case E.projectCon env {sgn = sgn, str = str, field = s} of
NONE => (conError env (UnboundCon (loc, s));
kerror)
| SOME (k, _) => k
in
((L'.CModProj (n, ms, s), loc), k)
end)
| L.CApp (c1, c2) =>
let
val (c1', k1) = elabCon env c1
val (c2', k2) = elabCon env c2
val dom = kunif loc
val ran = kunif loc
in
checkKind env c1' k1 (L'.KArrow (dom, ran), loc);
checkKind env c2' k2 dom;
((L'.CApp (c1', c2'), loc), ran)
end
| L.CAbs (x, ko, t) =>
let
val k' = case ko of
NONE => kunif loc
| SOME k => elabKind k
val env' = E.pushCRel env x k'
val (t', tk) = elabCon env' t
in
((L'.CAbs (x, k', t'), loc),
(L'.KArrow (k', tk), loc))
end
| L.CName s =>
((L'.CName s, loc), kname)
| L.CRecord xcs =>
let
val k = kunif loc
val xcs' = map (fn (x, c) =>
let
val (x', xk) = elabCon env x
val (c', ck) = elabCon env c
in
checkKind env x' xk kname;
checkKind env c' ck k;
(x', c')
end) xcs
val rc = (L'.CRecord (k, xcs'), loc)
(* Add duplicate field checking later. *)
in
(rc, (L'.KRecord k, loc))
end
| L.CConcat (c1, c2) =>
let
val (c1', k1) = elabCon env c1
val (c2', k2) = elabCon env c2
val ku = kunif loc
val k = (L'.KRecord ku, loc)
in
checkKind env c1' k1 k;
checkKind env c2' k2 k;
((L'.CConcat (c1', c2'), loc), k)
end
| L.CFold =>
let
val dom = kunif loc
val ran = kunif loc
in
((L'.CFold (dom, ran), loc),
foldKind (dom, ran, loc))
end
| L.CWild k =>
let
val k' = elabKind k
in
(cunif (loc, k'), k')
end
fun kunifsRemain k =
case k of
L'.KUnif (_, _, ref NONE) => true
| _ => false
fun cunifsRemain c =
case c of
L'.CUnif (loc, _, _, ref NONE) => SOME loc
| _ => NONE
val kunifsInDecl = U.Decl.exists {kind = kunifsRemain,
con = fn _ => false,
exp = fn _ => false,
sgn_item = fn _ => false,
sgn = fn _ => false,
str = fn _ => false,
decl = fn _ => false}
val cunifsInDecl = U.Decl.search {kind = fn _ => NONE,
con = cunifsRemain,
exp = fn _ => NONE,
sgn_item = fn _ => NONE,
sgn = fn _ => NONE,
str = fn _ => NONE,
decl = fn _ => NONE}
fun occursCon r =
U.Con.exists {kind = fn _ => false,
con = fn L'.CUnif (_, _, _, r') => r = r'
| _ => false}
datatype cunify_error =
CKind of L'.kind * L'.kind * kunify_error
| COccursCheckFailed of L'.con * L'.con
| CIncompatible of L'.con * L'.con
| CExplicitness of L'.con * L'.con
| CKindof of L'.con
| CRecordFailure
exception CUnify' of cunify_error
fun cunifyError env err =
case err of
CKind (k1, k2, kerr) =>
(eprefaces "Kind unification failure"
[("Kind 1", p_kind k1),
("Kind 2", p_kind k2)];
kunifyError kerr)
| COccursCheckFailed (c1, c2) =>
eprefaces "Constructor occurs check failed"
[("Con 1", p_con env c1),
("Con 2", p_con env c2)]
| CIncompatible (c1, c2) =>
eprefaces "Incompatible constructors"
[("Con 1", p_con env c1),
("Con 2", p_con env c2)]
| CExplicitness (c1, c2) =>
eprefaces "Differing constructor function explicitness"
[("Con 1", p_con env c1),
("Con 2", p_con env c2)]
| CKindof c =>
eprefaces "Kind unification variable blocks kindof calculation"
[("Con", p_con env c)]
| CRecordFailure =>
eprefaces "Can't unify record constructors" []
exception SynUnif = E.SynUnif
val liftConInCon = E.liftConInCon
val subConInCon =
U.Con.mapB {kind = fn k => k,
con = fn (xn, rep) => fn c =>
case c of
L'.CRel xn' =>
(case Int.compare (xn', xn) of
EQUAL => #1 rep
| GREATER => L'.CRel (xn' - 1)
| LESS => c)
(*| L'.CUnif _ => raise SynUnif*)
| _ => c,
bind = fn ((xn, rep), U.Con.Rel _) => (xn+1, liftConInCon 0 rep)
| (ctx, _) => ctx}
fun subStrInSgn (m1, m2) =
U.Sgn.map {kind = fn k => k,
con = fn c as L'.CModProj (m1', ms, x) =>
if m1 = m1' then
L'.CModProj (m2, ms, x)
else
c
| c => c,
sgn_item = fn sgi => sgi,
sgn = fn sgn => sgn}
type record_summary = {
fields : (L'.con * L'.con) list,
unifs : (L'.con * L'.con option ref) list,
others : L'.con list
}
fun summaryToCon {fields, unifs, others} =
let
val c = (L'.CRecord (ktype, []), dummy)
val c = List.foldr (fn (c', c) => (L'.CConcat (c', c), dummy)) c others
val c = List.foldr (fn ((c', _), c) => (L'.CConcat (c', c), dummy)) c unifs
in
(L'.CConcat ((L'.CRecord (ktype, fields), dummy), c), dummy)
end
fun p_summary env s = p_con env (summaryToCon s)
exception CUnify of L'.con * L'.con * cunify_error
fun hnormKind (kAll as (k, _)) =
case k of
L'.KUnif (_, _, ref (SOME k)) => hnormKind k
| _ => kAll
fun kindof env (c, loc) =
case c of
L'.TFun _ => ktype
| L'.TCFun _ => ktype
| L'.TRecord _ => ktype
| L'.CRel xn => #2 (E.lookupCRel env xn)
| L'.CNamed xn => #2 (E.lookupCNamed env xn)
| L'.CModProj (n, ms, x) =>
let
val (_, sgn) = E.lookupStrNamed env n
val (str, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {sgn = sgn, str = str, field = m} of
NONE => raise Fail "kindof: Unknown substructure"
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
in
case E.projectCon env {sgn = sgn, str = str, field = x} of
NONE => raise Fail "kindof: Unknown con in structure"
| SOME (k, _) => k
end
| L'.CApp (c, _) =>
(case #1 (hnormKind (kindof env c)) of
L'.KArrow (_, k) => k
| L'.KError => kerror
| _ => raise CUnify' (CKindof c))
| L'.CAbs (x, k, c) => (L'.KArrow (k, kindof (E.pushCRel env x k) c), loc)
| L'.CName _ => kname
| L'.CRecord (k, _) => (L'.KRecord k, loc)
| L'.CConcat (c, _) => kindof env c
| L'.CFold (dom, ran) => foldKind (dom, ran, loc)
| L'.CError => kerror
| L'.CUnif (_, k, _, _) => k
fun unifyRecordCons env (c1, c2) =
let
val k1 = kindof env c1
val k2 = kindof env c2
in
unifyKinds k1 k2;
unifySummaries env (k1, recordSummary env c1, recordSummary env c2)
end
and recordSummary env c : record_summary =
case hnormCon env c of
(L'.CRecord (_, xcs), _) => {fields = xcs, unifs = [], others = []}
| (L'.CConcat (c1, c2), _) =>
let
val s1 = recordSummary env c1
val s2 = recordSummary env c2
in
{fields = #fields s1 @ #fields s2,
unifs = #unifs s1 @ #unifs s2,
others = #others s1 @ #others s2}
end
| (L'.CUnif (_, _, _, ref (SOME c)), _) => recordSummary env c
| c' as (L'.CUnif (_, _, _, r), _) => {fields = [], unifs = [(c', r)], others = []}
| c' => {fields = [], unifs = [], others = [c']}
and consEq env (c1, c2) =
(unifyCons env c1 c2;
true)
handle CUnify _ => false
and consNeq env (c1, c2) =
case (#1 (hnormCon env c1), #1 (hnormCon env c2)) of
(L'.CName x1, L'.CName x2) => x1 <> x2
| _ => false
and unifySummaries env (k, s1 : record_summary, s2 : record_summary) =
let
(*val () = eprefaces "Summaries" [("#1", p_summary env s1),
("#2", p_summary env s2)]*)
fun eatMatching p (ls1, ls2) =
let
fun em (ls1, ls2, passed1) =
case ls1 of
[] => (rev passed1, ls2)
| h1 :: t1 =>
let
fun search (ls2', passed2) =
case ls2' of
[] => em (t1, ls2, h1 :: passed1)
| h2 :: t2 =>
if p (h1, h2) then
em (t1, List.revAppend (passed2, t2), passed1)
else
search (t2, h2 :: passed2)
in
search (ls2, [])
end
in
em (ls1, ls2, [])
end
val (fs1, fs2) = eatMatching (fn ((x1, c1), (x2, c2)) =>
not (consNeq env (x1, x2))
andalso consEq env (c1, c2)
andalso consEq env (x1, x2))
(#fields s1, #fields s2)
(*val () = eprefaces "Summaries2" [("#1", p_summary env {fields = fs1, unifs = #unifs s1, others = #others s1}),
("#2", p_summary env {fields = fs2, unifs = #unifs s2, others = #others s2})]*)
val (unifs1, unifs2) = eatMatching (fn ((_, r1), (_, r2)) => r1 = r2) (#unifs s1, #unifs s2)
val (others1, others2) = eatMatching (consEq env) (#others s1, #others s2)
fun unifFields (fs, others, unifs) =
case (fs, others, unifs) of
([], [], _) => ([], [], unifs)
| (_, _, []) => (fs, others, [])
| (_, _, (_, r) :: rest) =>
let
val r' = ref NONE
val cr' = (L'.CUnif (dummy, k, "recd", r'), dummy)
val prefix = case (fs, others) of
([], other :: others) =>
List.foldl (fn (other, c) =>
(L'.CConcat (c, other), dummy))
other others
| (fs, []) =>
(L'.CRecord (k, fs), dummy)
| (fs, others) =>
List.foldl (fn (other, c) =>
(L'.CConcat (c, other), dummy))
(L'.CRecord (k, fs), dummy) others
in
r := SOME (L'.CConcat (prefix, cr'), dummy);
([], [], (cr', r') :: rest)
end
val (fs1, others1, unifs2) = unifFields (fs1, others1, unifs2)
val (fs2, others2, unifs1) = unifFields (fs2, others2, unifs1)
val clear1 = case (fs1, others1) of
([], []) => true
| _ => false
val clear2 = case (fs2, others2) of
([], []) => true
| _ => false
val empty = (L'.CRecord (k, []), dummy)
fun pairOffUnifs (unifs1, unifs2) =
case (unifs1, unifs2) of
([], _) =>
if clear1 then
List.app (fn (_, r) => r := SOME empty) unifs2
else
raise CUnify' CRecordFailure
| (_, []) =>
if clear2 then
List.app (fn (_, r) => r := SOME empty) unifs1
else
raise CUnify' CRecordFailure
| ((c1, _) :: rest1, (_, r2) :: rest2) =>
(r2 := SOME c1;
pairOffUnifs (rest1, rest2))
in
pairOffUnifs (unifs1, unifs2)
end
and hnormCon env (cAll as (c, loc)) =
case c of
L'.CUnif (_, _, _, ref (SOME c)) => hnormCon env c
| L'.CNamed xn =>
(case E.lookupCNamed env xn of
(_, _, SOME c') => hnormCon env c'
| _ => cAll)
| L'.CModProj (n, ms, x) =>
let
val (_, sgn) = E.lookupStrNamed env n
val (str, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {sgn = sgn, str = str, field = m} of
NONE => raise Fail "hnormCon: Unknown substructure"
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
in
case E.projectCon env {sgn = sgn, str = str, field = x} of
NONE => raise Fail "kindof: Unknown con in structure"
| SOME (_, NONE) => cAll
| SOME (_, SOME c) => hnormCon env c
end
| L'.CApp (c1, c2) =>
(case #1 (hnormCon env c1) of
L'.CAbs (x, k, cb) =>
let
val sc = (hnormCon env (subConInCon (0, c2) cb))
handle SynUnif => cAll
(*val env' = E.pushCRel env x k*)
in
(*eprefaces "Subst" [("x", Print.PD.string x),
("cb", p_con env' cb),
("c2", p_con env c2),
("sc", p_con env sc)];*)
sc
end
| L'.CApp (c', i) =>
(case #1 (hnormCon env c') of
L'.CApp (c', f) =>
(case #1 (hnormCon env c') of
L'.CFold ks =>
(case #1 (hnormCon env c2) of
L'.CRecord (_, []) => hnormCon env i
| L'.CRecord (k, (x, c) :: rest) =>
hnormCon env
(L'.CApp ((L'.CApp ((L'.CApp (f, x), loc), c), loc),
(L'.CApp ((L'.CApp ((L'.CApp ((L'.CFold ks, loc), f), loc), i), loc),
(L'.CRecord (k, rest), loc)), loc)), loc)
| L'.CConcat ((L'.CRecord (k, (x, c) :: rest), _), rest') =>
let
val rest'' = (L'.CConcat ((L'.CRecord (k, rest), loc), rest'), loc)
(*val ccc = (L'.CApp ((L'.CApp ((L'.CApp (f, x), loc), c), loc),
(L'.CApp ((L'.CApp ((L'.CApp ((L'.CFold ks, loc), f), loc), i), loc),
rest''), loc)), loc)*)
in
(*eprefaces "Red to" [("ccc", p_con env ccc), ("ccc'", p_con env (hnormCon env ccc))];*)
hnormCon env
(L'.CApp ((L'.CApp ((L'.CApp (f, x), loc), c), loc),
(L'.CApp ((L'.CApp ((L'.CApp ((L'.CFold ks, loc), f), loc), i), loc),
rest''), loc)), loc)
end
| _ => cAll)
| _ => cAll)
| _ => cAll)
| _ => cAll)
| L'.CConcat (c1, c2) =>
(case (hnormCon env c1, hnormCon env c2) of
((L'.CRecord (k, xcs1), loc), (L'.CRecord (_, xcs2), _)) =>
(L'.CRecord (k, xcs1 @ xcs2), loc)
| ((L'.CRecord (_, []), _), c2') => c2'
| ((L'.CConcat (c11, c12), loc), c2') =>
hnormCon env (L'.CConcat (c11, (L'.CConcat (c12, c2'), loc)), loc)
| _ => cAll)
| _ => cAll
and unifyCons' env c1 c2 =
unifyCons'' env (hnormCon env c1) (hnormCon env c2)
and unifyCons'' env (c1All as (c1, _)) (c2All as (c2, _)) =
let
fun err f = raise CUnify' (f (c1All, c2All))
fun isRecord () = unifyRecordCons env (c1All, c2All)
in
case (c1, c2) of
(L'.TFun (d1, r1), L'.TFun (d2, r2)) =>
(unifyCons' env d1 d2;
unifyCons' env r1 r2)
| (L'.TCFun (expl1, x1, d1, r1), L'.TCFun (expl2, _, d2, r2)) =>
if expl1 <> expl2 then
err CExplicitness
else
(unifyKinds d1 d2;
unifyCons' (E.pushCRel env x1 d1) r1 r2)
| (L'.TRecord r1, L'.TRecord r2) => unifyCons' env r1 r2
| (L'.CRel n1, L'.CRel n2) =>
if n1 = n2 then
()
else
err CIncompatible
| (L'.CNamed n1, L'.CNamed n2) =>
if n1 = n2 then
()
else
err CIncompatible
| (L'.CApp (d1, r1), L'.CApp (d2, r2)) =>
(unifyCons' env d1 d2;
unifyCons' env r1 r2)
| (L'.CAbs (x1, k1, c1), L'.CAbs (_, k2, c2)) =>
(unifyKinds k1 k2;
unifyCons' (E.pushCRel env x1 k1) c1 c2)
| (L'.CName n1, L'.CName n2) =>
if n1 = n2 then
()
else
err CIncompatible
| (L'.CModProj (n1, ms1, x1), L'.CModProj (n2, ms2, x2)) =>
if n1 = n2 andalso ms1 = ms2 andalso x1 = x2 then
()
else
err CIncompatible
| (L'.CError, _) => ()
| (_, L'.CError) => ()
| (L'.CUnif (_, _, _, ref (SOME c1All)), _) => unifyCons' env c1All c2All
| (_, L'.CUnif (_, _, _, ref (SOME c2All))) => unifyCons' env c1All c2All
| (L'.CUnif (_, k1, _, r1), L'.CUnif (_, k2, _, r2)) =>
if r1 = r2 then
()
else
(unifyKinds k1 k2;
r1 := SOME c2All)
| (L'.CUnif (_, _, _, r), _) =>
if occursCon r c2All then
err COccursCheckFailed
else
r := SOME c2All
| (_, L'.CUnif (_, _, _, r)) =>
if occursCon r c1All then
err COccursCheckFailed
else
r := SOME c1All
| (L'.CRecord _, _) => isRecord ()
| (_, L'.CRecord _) => isRecord ()
| (L'.CConcat _, _) => isRecord ()
| (_, L'.CConcat _) => isRecord ()
| (L'.CFold (dom1, ran1), L'.CFold (dom2, ran2)) =>
(unifyKinds dom1 dom2;
unifyKinds ran1 ran2)
| _ => err CIncompatible
end
and unifyCons env c1 c2 =
unifyCons' env c1 c2
handle CUnify' err => raise CUnify (c1, c2, err)
| KUnify args => raise CUnify (c1, c2, CKind args)
datatype exp_error =
UnboundExp of ErrorMsg.span * string
| UnboundStrInExp of ErrorMsg.span * string
| Unify of L'.exp * L'.con * L'.con * cunify_error
| Unif of string * L'.con
| WrongForm of string * L'.exp * L'.con
fun expError env err =
case err of
UnboundExp (loc, s) =>
ErrorMsg.errorAt loc ("Unbound expression variable " ^ s)
| UnboundStrInExp (loc, s) =>
ErrorMsg.errorAt loc ("Unbound structure " ^ s)
| Unify (e, c1, c2, uerr) =>
(ErrorMsg.errorAt (#2 e) "Unification failure";
eprefaces' [("Expression", p_exp env e),
("Have con", p_con env c1),
("Need con", p_con env c2)];
cunifyError env uerr)
| Unif (action, c) =>
(ErrorMsg.errorAt (#2 c) ("Unification variable blocks " ^ action);
eprefaces' [("Con", p_con env c)])
| WrongForm (variety, e, t) =>
(ErrorMsg.errorAt (#2 e) ("Expression is not a " ^ variety);
eprefaces' [("Expression", p_exp env e),
("Type", p_con env t)])
fun checkCon env e c1 c2 =
unifyCons env c1 c2
handle CUnify (c1, c2, err) =>
expError env (Unify (e, c1, c2, err))
fun primType env p =
case p of
P.Int _ => !int
| P.Float _ => !float
| P.String _ => !string
fun recCons (k, nm, v, rest, loc) =
(L'.CConcat ((L'.CRecord (k, [(nm, v)]), loc),
rest), loc)
fun foldType (dom, loc) =
(L'.TCFun (L'.Explicit, "ran", (L'.KArrow ((L'.KRecord dom, loc), (L'.KType, loc)), loc),
(L'.TFun ((L'.TCFun (L'.Explicit, "nm", (L'.KName, loc),
(L'.TCFun (L'.Explicit, "v", dom,
(L'.TCFun (L'.Explicit, "rest", (L'.KRecord dom, loc),
(L'.TFun ((L'.CApp ((L'.CRel 3, loc), (L'.CRel 0, loc)), loc),
(L'.CApp ((L'.CRel 3, loc),
recCons (dom,
(L'.CRel 2, loc),
(L'.CRel 1, loc),
(L'.CRel 0, loc),
loc)), loc)), loc)),
loc)), loc)), loc),
(L'.TFun ((L'.CApp ((L'.CRel 0, loc), (L'.CRecord (dom, []), loc)), loc),
(L'.TCFun (L'.Explicit, "r", (L'.KRecord dom, loc),
(L'.CApp ((L'.CRel 1, loc), (L'.CRel 0, loc)), loc)), loc)),
loc)), loc)), loc)
fun typeof env (e, loc) =
case e of
L'.EPrim p => primType env p
| L'.ERel n => #2 (E.lookupERel env n)
| L'.ENamed n => #2 (E.lookupENamed env n)
| L'.EModProj (n, ms, x) =>
let
val (_, sgn) = E.lookupStrNamed env n
val (str, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {sgn = sgn, str = str, field = m} of
NONE => raise Fail "kindof: Unknown substructure"
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
in
case E.projectVal env {sgn = sgn, str = str, field = x} of
NONE => raise Fail "typeof: Unknown val in structure"
| SOME t => t
end
| L'.EApp (e1, _) =>
(case #1 (typeof env e1) of
L'.TFun (_, c) => c
| _ => raise Fail "typeof: Bad EApp")
| L'.EAbs (_, _, ran, _) => ran
| L'.ECApp (e1, c) =>
(case #1 (typeof env e1) of
L'.TCFun (_, _, _, c1) => subConInCon (0, c) c1
| _ => raise Fail "typeof: Bad ECApp")
| L'.ECAbs (expl, x, k, e1) => (L'.TCFun (expl, x, k, typeof (E.pushCRel env x k) e1), loc)
| L'.ERecord xes => (L'.TRecord (L'.CRecord (ktype, map (fn (x, _, t) => (x, t)) xes), loc), loc)
| L'.EField (_, _, {field, ...}) => field
| L'.EFold dom => foldType (dom, loc)
| L'.EError => cerror
fun elabHead env (e as (_, loc)) t =
let
fun unravel (t, e) =
case hnormCon env t of
(L'.TCFun (L'.Implicit, x, k, t'), _) =>
let
val u = cunif (loc, k)
in
unravel (subConInCon (0, u) t',
(L'.ECApp (e, u), loc))
end
| _ => (e, t)
in
unravel (t, e)
end
fun elabExp env (e, loc) =
case e of
L.EAnnot (e, t) =>
let
val (e', et) = elabExp env e
val (t', _) = elabCon env t
in
checkCon env e' et t';
(e', t')
end
| L.EPrim p => ((L'.EPrim p, loc), primType env p)
| L.EVar ([], s) =>
(case E.lookupE env s of
E.NotBound =>
(expError env (UnboundExp (loc, s));
(eerror, cerror))
| E.Rel (n, t) => ((L'.ERel n, loc), t)
| E.Named (n, t) => ((L'.ENamed n, loc), t))
| L.EVar (m1 :: ms, s) =>
(case E.lookupStr env m1 of
NONE => (expError env (UnboundStrInExp (loc, m1));
(eerror, cerror))
| SOME (n, sgn) =>
let
val (str, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {sgn = sgn, str = str, field = m} of
NONE => (conError env (UnboundStrInCon (loc, m));
(strerror, sgnerror))
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
val t = case E.projectVal env {sgn = sgn, str = str, field = s} of
NONE => (expError env (UnboundExp (loc, s));
cerror)
| SOME t => t
in
((L'.EModProj (n, ms, s), loc), t)
end)
| L.EApp (e1, e2) =>
let
val (e1', t1) = elabExp env e1
val (e1', t1) = elabHead env e1' t1
val (e2', t2) = elabExp env e2
val dom = cunif (loc, ktype)
val ran = cunif (loc, ktype)
val t = (L'.TFun (dom, ran), dummy)
in
checkCon env e1' t1 t;
checkCon env e2' t2 dom;
((L'.EApp (e1', e2'), loc), ran)
end
| L.EAbs (x, to, e) =>
let
val t' = case to of
NONE => cunif (loc, ktype)
| SOME t =>
let
val (t', tk) = elabCon env t
in
checkKind env t' tk ktype;
t'
end
val (e', et) = elabExp (E.pushERel env x t') e
in
((L'.EAbs (x, t', et, e'), loc),
(L'.TFun (t', et), loc))
end
| L.ECApp (e, c) =>
let
val (e', et) = elabExp env e
val (e', et) = elabHead env e' et
val (c', ck) = elabCon env c
in
case #1 (hnormCon env et) of
L'.CError => (eerror, cerror)
| L'.TCFun (_, _, k, eb) =>
let
val () = checkKind env c' ck k
val eb' = subConInCon (0, c') eb
handle SynUnif => (expError env (Unif ("substitution", eb));
cerror)
in
((L'.ECApp (e', c'), loc), eb')
end
| L'.CUnif _ =>
(expError env (Unif ("application", et));
(eerror, cerror))
| _ =>
(expError env (WrongForm ("constructor function", e', et));
(eerror, cerror))
end
| L.ECAbs (expl, x, k, e) =>
let
val expl' = elabExplicitness expl
val k' = elabKind k
val (e', et) = elabExp (E.pushCRel env x k') e
in
((L'.ECAbs (expl', x, k', e'), loc),
(L'.TCFun (expl', x, k', et), loc))
end
| L.ERecord xes =>
let
val xes' = map (fn (x, e) =>
let
val (x', xk) = elabCon env x
val (e', et) = elabExp env e
in
checkKind env x' xk kname;
(x', e', et)
end) xes
in
((L'.ERecord xes', loc),
(L'.TRecord (L'.CRecord (ktype, map (fn (x', _, et) => (x', et)) xes'), loc), loc))
end
| L.EField (e, c) =>
let
val (e', et) = elabExp env e
val (c', ck) = elabCon env c
val ft = cunif (loc, ktype)
val rest = cunif (loc, ktype_record)
in
checkKind env c' ck kname;
checkCon env e' et (L'.TRecord (L'.CConcat ((L'.CRecord (ktype, [(c', ft)]), loc), rest), loc), loc);
((L'.EField (e', c', {field = ft, rest = rest}), loc), ft)
end
| L.EFold =>
let
val dom = kunif loc
in
((L'.EFold dom, loc), foldType (dom, loc))
end
datatype decl_error =
KunifsRemain of ErrorMsg.span
| CunifsRemain of ErrorMsg.span
fun declError env err =
case err of
KunifsRemain loc =>
ErrorMsg.errorAt loc "Some kind unification variables are undetermined in declaration"
| CunifsRemain loc =>
ErrorMsg.errorAt loc "Some constructor unification variables are undetermined in declaration"
datatype sgn_error =
UnboundSgn of ErrorMsg.span * string
| UnmatchedSgi of L'.sgn_item
| SgiWrongKind of L'.sgn_item * L'.kind * L'.sgn_item * L'.kind * kunify_error
| SgiWrongCon of L'.sgn_item * L'.con * L'.sgn_item * L'.con * cunify_error
| SgnWrongForm of L'.sgn * L'.sgn
| UnWhereable of L'.sgn * string
| WhereWrongKind of L'.kind * L'.kind * kunify_error
| NotIncludable of L'.sgn
| DuplicateCon of ErrorMsg.span * string
| DuplicateVal of ErrorMsg.span * string
| DuplicateSgn of ErrorMsg.span * string
| DuplicateStr of ErrorMsg.span * string
fun sgnError env err =
case err of
UnboundSgn (loc, s) =>
ErrorMsg.errorAt loc ("Unbound signature variable " ^ s)
| UnmatchedSgi (sgi as (_, loc)) =>
(ErrorMsg.errorAt loc "Unmatched signature item";
eprefaces' [("Item", p_sgn_item env sgi)])
| SgiWrongKind (sgi1, k1, sgi2, k2, kerr) =>
(ErrorMsg.errorAt (#2 sgi1) "Kind unification failure in signature matching:";
eprefaces' [("Have", p_sgn_item env sgi1),
("Need", p_sgn_item env sgi2),
("Kind 1", p_kind k1),
("Kind 2", p_kind k2)];
kunifyError kerr)
| SgiWrongCon (sgi1, c1, sgi2, c2, cerr) =>
(ErrorMsg.errorAt (#2 sgi1) "Constructor unification failure in signature matching:";
eprefaces' [("Have", p_sgn_item env sgi1),
("Need", p_sgn_item env sgi2),
("Con 1", p_con env c1),
("Con 2", p_con env c2)];
cunifyError env cerr)
| SgnWrongForm (sgn1, sgn2) =>
(ErrorMsg.errorAt (#2 sgn1) "Incompatible signatures:";
eprefaces' [("Sig 1", p_sgn env sgn1),
("Sig 2", p_sgn env sgn2)])
| UnWhereable (sgn, x) =>
(ErrorMsg.errorAt (#2 sgn) "Unavailable field for 'where'";
eprefaces' [("Signature", p_sgn env sgn),
("Field", PD.string x)])
| WhereWrongKind (k1, k2, kerr) =>
(ErrorMsg.errorAt (#2 k1) "Wrong kind for 'where'";
eprefaces' [("Have", p_kind k1),
("Need", p_kind k2)];
kunifyError kerr)
| NotIncludable sgn =>
(ErrorMsg.errorAt (#2 sgn) "Invalid signature to 'include'";
eprefaces' [("Signature", p_sgn env sgn)])
| DuplicateCon (loc, s) =>
ErrorMsg.errorAt loc ("Duplicate constructor " ^ s ^ " in signature")
| DuplicateVal (loc, s) =>
ErrorMsg.errorAt loc ("Duplicate value " ^ s ^ " in signature")
| DuplicateSgn (loc, s) =>
ErrorMsg.errorAt loc ("Duplicate signature " ^ s ^ " in signature")
| DuplicateStr (loc, s) =>
ErrorMsg.errorAt loc ("Duplicate structure " ^ s ^ " in signature")
datatype str_error =
UnboundStr of ErrorMsg.span * string
| NotFunctor of L'.sgn
| FunctorRebind of ErrorMsg.span
| UnOpenable of L'.sgn
| NotType of L'.kind * (L'.kind * L'.kind * kunify_error)
fun strError env err =
case err of
UnboundStr (loc, s) =>
ErrorMsg.errorAt loc ("Unbound structure variable " ^ s)
| NotFunctor sgn =>
(ErrorMsg.errorAt (#2 sgn) "Application of non-functor";
eprefaces' [("Signature", p_sgn env sgn)])
| FunctorRebind loc =>
ErrorMsg.errorAt loc "Attempt to rebind functor"
| UnOpenable sgn =>
(ErrorMsg.errorAt (#2 sgn) "Un-openable structure";
eprefaces' [("Signature", p_sgn env sgn)])
| NotType (k, (k1, k2, ue)) =>
(ErrorMsg.errorAt (#2 k) "'val' type kind is not 'Type'";
eprefaces' [("Kind", p_kind k),
("Subkind 1", p_kind k1),
("Subkind 2", p_kind k2)];
kunifyError ue)
val hnormSgn = E.hnormSgn
fun elabSgn_item ((sgi, loc), env) =
case sgi of
L.SgiConAbs (x, k) =>
let
val k' = elabKind k
val (env', n) = E.pushCNamed env x k' NONE
in
([(L'.SgiConAbs (x, n, k'), loc)], env')
end
| L.SgiCon (x, ko, c) =>
let
val k' = case ko of
NONE => kunif loc
| SOME k => elabKind k
val (c', ck) = elabCon env c
val (env', n) = E.pushCNamed env x k' (SOME c')
in
checkKind env c' ck k';
([(L'.SgiCon (x, n, k', c'), loc)], env')
end
| L.SgiVal (x, c) =>
let
val (c', ck) = elabCon env c
val (env', n) = E.pushENamed env x c'
in
(unifyKinds ck ktype
handle KUnify ue => strError env (NotType (ck, ue)));
([(L'.SgiVal (x, n, c'), loc)], env')
end
| L.SgiStr (x, sgn) =>
let
val sgn' = elabSgn env sgn
val (env', n) = E.pushStrNamed env x sgn'
in
([(L'.SgiStr (x, n, sgn'), loc)], env')
end
| L.SgiSgn (x, sgn) =>
let
val sgn' = elabSgn env sgn
val (env', n) = E.pushSgnNamed env x sgn'
in
([(L'.SgiSgn (x, n, sgn'), loc)], env')
end
| L.SgiInclude sgn =>
let
val sgn' = elabSgn env sgn
in
case #1 (hnormSgn env sgn') of
L'.SgnConst sgis =>
(sgis, foldl (fn (sgi, env) => E.sgiBinds env sgi) env sgis)
| _ => (sgnError env (NotIncludable sgn');
([], env))
end
and elabSgn env (sgn, loc) =
case sgn of
L.SgnConst sgis =>
let
val (sgis', _) = ListUtil.foldlMapConcat elabSgn_item env sgis
val _ = foldl (fn ((sgi, loc), (cons, vals, sgns, strs)) =>
case sgi of
L'.SgiConAbs (x, _, _) =>
(if SS.member (cons, x) then
sgnError env (DuplicateCon (loc, x))
else
();
(SS.add (cons, x), vals, sgns, strs))
| L'.SgiCon (x, _, _, _) =>
(if SS.member (cons, x) then
sgnError env (DuplicateCon (loc, x))
else
();
(SS.add (cons, x), vals, sgns, strs))
| L'.SgiVal (x, _, _) =>
(if SS.member (vals, x) then
sgnError env (DuplicateVal (loc, x))
else
();
(cons, SS.add (vals, x), sgns, strs))
| L'.SgiSgn (x, _, _) =>
(if SS.member (sgns, x) then
sgnError env (DuplicateSgn (loc, x))
else
();
(cons, vals, SS.add (sgns, x), strs))
| L'.SgiStr (x, _, _) =>
(if SS.member (strs, x) then
sgnError env (DuplicateStr (loc, x))
else
();
(cons, vals, sgns, SS.add (strs, x))))
(SS.empty, SS.empty, SS.empty, SS.empty) sgis'
in
(L'.SgnConst sgis', loc)
end
| L.SgnVar x =>
(case E.lookupSgn env x of
NONE =>
(sgnError env (UnboundSgn (loc, x));
(L'.SgnError, loc))
| SOME (n, sgis) => (L'.SgnVar n, loc))
| L.SgnFun (m, dom, ran) =>
let
val dom' = elabSgn env dom
val (env', n) = E.pushStrNamed env m dom'
val ran' = elabSgn env' ran
in
(L'.SgnFun (m, n, dom', ran'), loc)
end
| L.SgnWhere (sgn, x, c) =>
let
val sgn' = elabSgn env sgn
val (c', ck) = elabCon env c
in
case #1 (hnormSgn env sgn') of
L'.SgnError => sgnerror
| L'.SgnConst sgis =>
if List.exists (fn (L'.SgiConAbs (x', _, k), _) =>
x' = x andalso
(unifyKinds k ck
handle KUnify x => sgnError env (WhereWrongKind x);
true)
| _ => false) sgis then
(L'.SgnWhere (sgn', x, c'), loc)
else
(sgnError env (UnWhereable (sgn', x));
sgnerror)
| _ => (sgnError env (UnWhereable (sgn', x));
sgnerror)
end
| L.SgnProj (m, ms, x) =>
(case E.lookupStr env m of
NONE => (strError env (UnboundStr (loc, m));
sgnerror)
| SOME (n, sgn) =>
let
val (str, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {sgn = sgn, str = str, field = m} of
NONE => (strError env (UnboundStr (loc, m));
(strerror, sgnerror))
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
in
case E.projectSgn env {sgn = sgn, str = str, field = x} of
NONE => (sgnError env (UnboundSgn (loc, x));
sgnerror)
| SOME _ => (L'.SgnProj (n, ms, x), loc)
end)
fun selfify env {str, strs, sgn} =
case #1 (hnormSgn env sgn) of
L'.SgnError => sgn
| L'.SgnVar _ => sgn
| L'.SgnConst sgis =>
(L'.SgnConst (map (fn (L'.SgiConAbs (x, n, k), loc) =>
(L'.SgiCon (x, n, k, (L'.CModProj (str, strs, x), loc)), loc)
| (L'.SgiStr (x, n, sgn), loc) =>
(L'.SgiStr (x, n, selfify env {str = str, strs = strs @ [x], sgn = sgn}), loc)
| x => x) sgis), #2 sgn)
| L'.SgnFun _ => sgn
| L'.SgnWhere _ => sgn
| L'.SgnProj (m, ms, x) =>
case E.projectSgn env {str = foldl (fn (m, str) => (L'.StrProj (str, m), #2 sgn))
(L'.StrVar m, #2 sgn) ms,
sgn = #2 (E.lookupStrNamed env m),
field = x} of
NONE => raise Fail "Elaborate.selfify: projectSgn returns NONE"
| SOME sgn => selfify env {str = str, strs = strs, sgn = sgn}
fun selfifyAt env {str, sgn} =
let
fun self (str, _) =
case str of
L'.StrVar x => SOME (x, [])
| L'.StrProj (str, x) =>
(case self str of
NONE => NONE
| SOME (m, ms) => SOME (m, ms @ [x]))
| _ => NONE
in
case self str of
NONE => sgn
| SOME (str, strs) => selfify env {sgn = sgn, str = str, strs = strs}
end
fun dopen env {str, strs, sgn} =
let
val m = foldl (fn (m, str) => (L'.StrProj (str, m), #2 sgn))
(L'.StrVar str, #2 sgn) strs
in
case #1 (hnormSgn env sgn) of
L'.SgnConst sgis =>
ListUtil.foldlMap (fn ((sgi, loc), env') =>
case sgi of
L'.SgiConAbs (x, n, k) =>
((L'.DCon (x, n, k, (L'.CModProj (str, strs, x), loc)), loc),
E.pushCNamedAs env' x n k NONE)
| L'.SgiCon (x, n, k, c) =>
((L'.DCon (x, n, k, (L'.CModProj (str, strs, x), loc)), loc),
E.pushCNamedAs env' x n k (SOME c))
| L'.SgiVal (x, n, t) =>
((L'.DVal (x, n, t, (L'.EModProj (str, strs, x), loc)), loc),
E.pushENamedAs env' x n t)
| L'.SgiStr (x, n, sgn) =>
((L'.DStr (x, n, sgn, (L'.StrProj (m, x), loc)), loc),
E.pushStrNamedAs env' x n sgn)
| L'.SgiSgn (x, n, sgn) =>
((L'.DSgn (x, n, (L'.SgnProj (str, strs, x), loc)), loc),
E.pushSgnNamedAs env' x n sgn))
env sgis
| _ => (strError env (UnOpenable sgn);
([], env))
end
fun sgiOfDecl (d, loc) =
case d of
L'.DCon (x, n, k, c) => (L'.SgiCon (x, n, k, c), loc)
| L'.DVal (x, n, t, _) => (L'.SgiVal (x, n, t), loc)
| L'.DSgn (x, n, sgn) => (L'.SgiSgn (x, n, sgn), loc)
| L'.DStr (x, n, sgn, _) => (L'.SgiStr (x, n, sgn), loc)
| L'.DFfiStr (x, n, sgn) => (L'.SgiStr (x, n, sgn), loc)
fun subSgn env sgn1 (sgn2 as (_, loc2)) =
case (#1 (hnormSgn env sgn1), #1 (hnormSgn env sgn2)) of
(L'.SgnError, _) => ()
| (_, L'.SgnError) => ()
| (L'.SgnConst sgis1, L'.SgnConst sgis2) =>
let
fun folder (sgi2All as (sgi, _), env) =
let
fun seek p =
let
fun seek env ls =
case ls of
[] => (sgnError env (UnmatchedSgi sgi2All);
env)
| h :: t =>
case p h of
NONE => seek (E.sgiBinds env h) t
| SOME env => env
in
seek env sgis1
end
in
case sgi of
L'.SgiConAbs (x, n2, k2) =>
seek (fn sgi1All as (sgi1, _) =>
let
fun found (x', n1, k1, co1) =
if x = x' then
let
val () = unifyKinds k1 k2
handle KUnify (k1, k2, err) =>
sgnError env (SgiWrongKind (sgi1All, k1, sgi2All, k2, err))
val env = E.pushCNamedAs env x n1 k1 co1
in
SOME (if n1 = n2 then
env
else
E.pushCNamedAs env x n2 k2 (SOME (L'.CNamed n1, loc2)))
end
else
NONE
in
case sgi1 of
L'.SgiConAbs (x', n1, k1) => found (x', n1, k1, NONE)
| L'.SgiCon (x', n1, k1, c1) => found (x', n1, k1, SOME c1)
| _ => NONE
end)
| L'.SgiCon (x, n2, k2, c2) =>
seek (fn sgi1All as (sgi1, _) =>
case sgi1 of
L'.SgiCon (x', n1, k1, c1) =>
if x = x' then
let
val () = unifyCons env c1 c2
handle CUnify (c1, c2, err) =>
sgnError env (SgiWrongCon (sgi1All, c1, sgi2All, c2, err))
in
SOME (E.pushCNamedAs env x n2 k2 (SOME c2))
end
else
NONE
| _ => NONE)
| L'.SgiVal (x, n2, c2) =>
seek (fn sgi1All as (sgi1, _) =>
case sgi1 of
L'.SgiVal (x', n1, c1) =>
if x = x' then
let
val () = unifyCons env c1 c2
handle CUnify (c1, c2, err) =>
sgnError env (SgiWrongCon (sgi1All, c1, sgi2All, c2, err))
in
SOME env
end
else
NONE
| _ => NONE)
| L'.SgiStr (x, n2, sgn2) =>
seek (fn sgi1All as (sgi1, _) =>
case sgi1 of
L'.SgiStr (x', n1, sgn1) =>
if x = x' then
let
val () = subSgn env sgn1 sgn2
val env = E.pushStrNamedAs env x n1 sgn1
val env = if n1 = n2 then
env
else
E.pushStrNamedAs env x n2
(selfifyAt env {str = (L'.StrVar n1, #2 sgn2),
sgn = sgn2})
in
SOME env
end
else
NONE
| _ => NONE)
| L'.SgiSgn (x, n2, sgn2) =>
seek (fn sgi1All as (sgi1, _) =>
case sgi1 of
L'.SgiSgn (x', n1, sgn1) =>
if x = x' then
let
val () = subSgn env sgn1 sgn2
val () = subSgn env sgn2 sgn1
val env = E.pushSgnNamedAs env x n2 sgn2
val env = if n1 = n2 then
env
else
E.pushSgnNamedAs env x n1 sgn2
in
SOME env
end
else
NONE
| _ => NONE)
end
in
ignore (foldl folder env sgis2)
end
| (L'.SgnFun (m1, n1, dom1, ran1), L'.SgnFun (m2, n2, dom2, ran2)) =>
let
val ran1 =
if n1 = n2 then
ran1
else
subStrInSgn (n1, n2) ran1
in
subSgn env dom2 dom1;
subSgn (E.pushStrNamedAs env m2 n2 dom2) ran1 ran2
end
| _ => sgnError env (SgnWrongForm (sgn1, sgn2))
fun elabDecl ((d, loc), env) =
case d of
L.DCon (x, ko, c) =>
let
val k' = case ko of
NONE => kunif loc
| SOME k => elabKind k
val (c', ck) = elabCon env c
val (env', n) = E.pushCNamed env x k' (SOME c')
in
checkKind env c' ck k';
([(L'.DCon (x, n, k', c'), loc)], env')
end
| L.DVal (x, co, e) =>
let
val (c', ck) = case co of
NONE => (cunif (loc, ktype), ktype)
| SOME c => elabCon env c
val (e', et) = elabExp env e
val (env', n) = E.pushENamed env x c'
in
checkCon env e' et c';
([(L'.DVal (x, n, c', e'), loc)], env')
end
| L.DSgn (x, sgn) =>
let
val sgn' = elabSgn env sgn
val (env', n) = E.pushSgnNamed env x sgn'
in
([(L'.DSgn (x, n, sgn'), loc)], env')
end
| L.DStr (x, sgno, str) =>
let
val formal = Option.map (elabSgn env) sgno
val (str', sgn') =
case formal of
NONE =>
let
val (str', actual) = elabStr env str
in
(str', selfifyAt env {str = str', sgn = actual})
end
| SOME formal =>
let
val str =
case #1 (hnormSgn env formal) of
L'.SgnConst sgis =>
(case #1 str of
L.StrConst ds =>
let
val needed = foldl (fn ((sgi, _), needed) =>
case sgi of
L'.SgiConAbs (x, _, _) => SS.add (needed, x)
| _ => needed)
SS.empty sgis
val needed = foldl (fn ((d, _), needed) =>
case d of
L.DCon (x, _, _) => (SS.delete (needed, x)
handle NotFound => needed)
| L.DOpen _ => SS.empty
| _ => needed)
needed ds
in
case SS.listItems needed of
[] => str
| xs =>
let
val kwild = (L.KWild, #2 str)
val cwild = (L.CWild kwild, #2 str)
val ds' = map (fn x => (L.DCon (x, NONE, cwild), #2 str)) xs
in
(L.StrConst (ds @ ds'), #2 str)
end
end
| _ => str)
| _ => str
val (str', actual) = elabStr env str
in
subSgn env actual formal;
(str', formal)
end
val (env', n) = E.pushStrNamed env x sgn'
in
case #1 (hnormSgn env sgn') of
L'.SgnFun _ =>
(case #1 str' of
L'.StrFun _ => ()
| _ => strError env (FunctorRebind loc))
| _ => ();
([(L'.DStr (x, n, sgn', str'), loc)], env')
end
| L.DFfiStr (x, sgn) =>
let
val sgn' = elabSgn env sgn
val (env', n) = E.pushStrNamed env x sgn'
in
([(L'.DFfiStr (x, n, sgn'), loc)], env')
end
| L.DOpen (m, ms) =>
case E.lookupStr env m of
NONE => (strError env (UnboundStr (loc, m));
([], env))
| SOME (n, sgn) =>
let
val (_, sgn) = foldl (fn (m, (str, sgn)) =>
case E.projectStr env {str = str, sgn = sgn, field = m} of
NONE => (strError env (UnboundStr (loc, m));
(strerror, sgnerror))
| SOME sgn => ((L'.StrProj (str, m), loc), sgn))
((L'.StrVar n, loc), sgn) ms
in
dopen env {str = n, strs = ms, sgn = sgn}
end
and elabStr env (str, loc) =
case str of
L.StrConst ds =>
let
val (ds', env') = ListUtil.foldlMapConcat elabDecl env ds
val sgis = map sgiOfDecl ds'
val (sgis, _, _, _, _) =
foldr (fn ((sgi, loc), (sgis, cons, vals, sgns, strs)) =>
case sgi of
L'.SgiConAbs (x, n, k) =>
let
val (cons, x) =
if SS.member (cons, x) then
(cons, "?" ^ x)
else
(SS.add (cons, x), x)
in
((L'.SgiConAbs (x, n, k), loc) :: sgis, cons, vals, sgns, strs)
end
| L'.SgiCon (x, n, k, c) =>
let
val (cons, x) =
if SS.member (cons, x) then
(cons, "?" ^ x)
else
(SS.add (cons, x), x)
in
((L'.SgiCon (x, n, k, c), loc) :: sgis, cons, vals, sgns, strs)
end
| L'.SgiVal (x, n, c) =>
let
val (vals, x) =
if SS.member (vals, x) then
(vals, "?" ^ x)
else
(SS.add (vals, x), x)
in
((L'.SgiVal (x, n, c), loc) :: sgis, cons, vals, sgns, strs)
end
| L'.SgiSgn (x, n, sgn) =>
let
val (sgns, x) =
if SS.member (sgns, x) then
(sgns, "?" ^ x)
else
(SS.add (sgns, x), x)
in
((L'.SgiSgn (x, n, sgn), loc) :: sgis, cons, vals, sgns, strs)
end
| L'.SgiStr (x, n, sgn) =>
let
val (strs, x) =
if SS.member (strs, x) then
(strs, "?" ^ x)
else
(SS.add (strs, x), x)
in
((L'.SgiStr (x, n, sgn), loc) :: sgis, cons, vals, sgns, strs)
end)
([], SS.empty, SS.empty, SS.empty, SS.empty) sgis
in
((L'.StrConst ds', loc), (L'.SgnConst sgis, loc))
end
| L.StrVar x =>
(case E.lookupStr env x of
NONE =>
(strError env (UnboundStr (loc, x));
(strerror, sgnerror))
| SOME (n, sgn) => ((L'.StrVar n, loc), sgn))
| L.StrProj (str, x) =>
let
val (str', sgn) = elabStr env str
in
case E.projectStr env {str = str', sgn = sgn, field = x} of
NONE => (strError env (UnboundStr (loc, x));
(strerror, sgnerror))
| SOME sgn => ((L'.StrProj (str', x), loc), sgn)
end
| L.StrFun (m, dom, ranO, str) =>
let
val dom' = elabSgn env dom
val (env', n) = E.pushStrNamed env m dom'
val (str', actual) = elabStr env' str
val formal =
case ranO of
NONE => actual
| SOME ran =>
let
val ran' = elabSgn env' ran
in
subSgn env' actual ran';
ran'
end
in
((L'.StrFun (m, n, dom', formal, str'), loc),
(L'.SgnFun (m, n, dom', formal), loc))
end
| L.StrApp (str1, str2) =>
let
val (str1', sgn1) = elabStr env str1
val (str2', sgn2) = elabStr env str2
in
case #1 (hnormSgn env sgn1) of
L'.SgnError => (strerror, sgnerror)
| L'.SgnFun (m, n, dom, ran) =>
(subSgn env sgn2 dom;
case #1 (hnormSgn env ran) of
L'.SgnError => (strerror, sgnerror)
| L'.SgnConst sgis =>
((L'.StrApp (str1', str2'), loc),
(L'.SgnConst ((L'.SgiStr (m, n, selfifyAt env {str = str2', sgn = sgn2}), loc) :: sgis), loc))
| _ => raise Fail "Unable to hnormSgn in functor application")
| _ => (strError env (NotFunctor sgn1);
(strerror, sgnerror))
end
fun elabFile basis env file =
let
val sgn = elabSgn env (L.SgnConst basis, ErrorMsg.dummySpan)
val (env', basis_n) = E.pushStrNamed env "Basis" sgn
val (ds, env') = dopen env' {str = basis_n, strs = [], sgn = sgn}
fun discoverC r x =
case E.lookupC env' x of
E.NotBound => raise Fail ("Constructor " ^ x ^ " unbound in Basis")
| E.Rel _ => raise Fail ("Constructor " ^ x ^ " bound relatively in Basis")
| E.Named (n, (_, loc)) => r := (L'.CNamed n, loc)
val () = discoverC int "int"
val () = discoverC float "float"
val () = discoverC string "string"
fun elabDecl' (d, env) =
let
val () = resetKunif ()
val () = resetCunif ()
val (ds, env) = elabDecl (d, env)
in
if ErrorMsg.anyErrors () then
()
else (
if List.exists kunifsInDecl ds then
declError env (KunifsRemain (#2 d))
else
();
case ListUtil.search cunifsInDecl ds of
NONE => ()
| SOME loc =>
declError env (CunifsRemain loc)
);
(ds, env)
end
val (file, _) = ListUtil.foldlMapConcat elabDecl' env' file
in
(L'.DFfiStr ("Basis", basis_n, sgn), ErrorMsg.dummySpan) :: ds @ file
end
end
|