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Elaborating 'where'
author Adam Chlipala <adamc@hcoop.net>
date Thu, 19 Jun 2008 16:35:40 -0400
parents 1405d8c26790
children d94c484337d0
rev   line source
adamc@2 1 (* Copyright (c) 2008, Adam Chlipala
adamc@2 2 * All rights reserved.
adamc@2 3 *
adamc@2 4 * Redistribution and use in source and binary forms, with or without
adamc@2 5 * modification, are permitted provided that the following conditions are met:
adamc@2 6 *
adamc@2 7 * - Redistributions of source code must retain the above copyright notice,
adamc@2 8 * this list of conditions and the following disclaimer.
adamc@2 9 * - Redistributions in binary form must reproduce the above copyright notice,
adamc@2 10 * this list of conditions and the following disclaimer in the documentation
adamc@2 11 * and/or other materials provided with the distribution.
adamc@2 12 * - The names of contributors may not be used to endorse or promote products
adamc@2 13 * derived from this software without specific prior written permission.
adamc@2 14 *
adamc@2 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@2 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@2 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@2 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@2 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
adamc@2 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@2 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@2 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@2 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@2 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@2 25 * POSSIBILITY OF SUCH DAMAGE.
adamc@2 26 *)
adamc@2 27
adamc@2 28 structure Elaborate :> ELABORATE = struct
adamc@2 29
adamc@14 30 structure P = Prim
adamc@4 31 structure L = Source
adamc@2 32 structure L' = Elab
adamc@2 33 structure E = ElabEnv
adamc@2 34 structure U = ElabUtil
adamc@2 35
adamc@3 36 open Print
adamc@3 37 open ElabPrint
adamc@3 38
adamc@2 39 fun elabExplicitness e =
adamc@2 40 case e of
adamc@2 41 L.Explicit => L'.Explicit
adamc@2 42 | L.Implicit => L'.Implicit
adamc@2 43
adamc@2 44 fun occursKind r =
adamc@2 45 U.Kind.exists (fn L'.KUnif (_, r') => r = r'
adamc@2 46 | _ => false)
adamc@2 47
adamc@3 48 datatype kunify_error =
adamc@2 49 KOccursCheckFailed of L'.kind * L'.kind
adamc@2 50 | KIncompatible of L'.kind * L'.kind
adamc@2 51
adamc@3 52 exception KUnify' of kunify_error
adamc@3 53
adamc@3 54 fun kunifyError err =
adamc@2 55 case err of
adamc@2 56 KOccursCheckFailed (k1, k2) =>
adamc@3 57 eprefaces "Kind occurs check failed"
adamc@3 58 [("Kind 1", p_kind k1),
adamc@3 59 ("Kind 2", p_kind k2)]
adamc@2 60 | KIncompatible (k1, k2) =>
adamc@3 61 eprefaces "Incompatible kinds"
adamc@3 62 [("Kind 1", p_kind k1),
adamc@3 63 ("Kind 2", p_kind k2)]
adamc@2 64
adamc@3 65 fun unifyKinds' (k1All as (k1, _)) (k2All as (k2, _)) =
adamc@2 66 let
adamc@3 67 fun err f = raise KUnify' (f (k1All, k2All))
adamc@2 68 in
adamc@2 69 case (k1, k2) of
adamc@2 70 (L'.KType, L'.KType) => ()
adamc@2 71 | (L'.KArrow (d1, r1), L'.KArrow (d2, r2)) =>
adamc@3 72 (unifyKinds' d1 d2;
adamc@3 73 unifyKinds' r1 r2)
adamc@2 74 | (L'.KName, L'.KName) => ()
adamc@3 75 | (L'.KRecord k1, L'.KRecord k2) => unifyKinds' k1 k2
adamc@2 76
adamc@2 77 | (L'.KError, _) => ()
adamc@2 78 | (_, L'.KError) => ()
adamc@2 79
adamc@3 80 | (L'.KUnif (_, ref (SOME k1All)), _) => unifyKinds' k1All k2All
adamc@3 81 | (_, L'.KUnif (_, ref (SOME k2All))) => unifyKinds' k1All k2All
adamc@2 82
adamc@2 83 | (L'.KUnif (_, r1), L'.KUnif (_, r2)) =>
adamc@2 84 if r1 = r2 then
adamc@2 85 ()
adamc@2 86 else
adamc@2 87 r1 := SOME k2All
adamc@2 88
adamc@2 89 | (L'.KUnif (_, r), _) =>
adamc@2 90 if occursKind r k2All then
adamc@2 91 err KOccursCheckFailed
adamc@2 92 else
adamc@2 93 r := SOME k2All
adamc@2 94 | (_, L'.KUnif (_, r)) =>
adamc@2 95 if occursKind r k1All then
adamc@2 96 err KOccursCheckFailed
adamc@2 97 else
adamc@2 98 r := SOME k1All
adamc@2 99
adamc@2 100 | _ => err KIncompatible
adamc@2 101 end
adamc@2 102
adamc@3 103 exception KUnify of L'.kind * L'.kind * kunify_error
adamc@3 104
adamc@3 105 fun unifyKinds k1 k2 =
adamc@3 106 unifyKinds' k1 k2
adamc@3 107 handle KUnify' err => raise KUnify (k1, k2, err)
adamc@3 108
adamc@3 109 datatype con_error =
adamc@3 110 UnboundCon of ErrorMsg.span * string
adamc@34 111 | UnboundStrInCon of ErrorMsg.span * string
adamc@3 112 | WrongKind of L'.con * L'.kind * L'.kind * kunify_error
adamc@3 113
adamc@5 114 fun conError env err =
adamc@3 115 case err of
adamc@3 116 UnboundCon (loc, s) =>
adamc@3 117 ErrorMsg.errorAt loc ("Unbound constructor variable " ^ s)
adamc@34 118 | UnboundStrInCon (loc, s) =>
adamc@34 119 ErrorMsg.errorAt loc ("Unbound structure " ^ s)
adamc@3 120 | WrongKind (c, k1, k2, kerr) =>
adamc@3 121 (ErrorMsg.errorAt (#2 c) "Wrong kind";
adamc@5 122 eprefaces' [("Constructor", p_con env c),
adamc@5 123 ("Have kind", p_kind k1),
adamc@5 124 ("Need kind", p_kind k2)];
adamc@3 125 kunifyError kerr)
adamc@3 126
adamc@5 127 fun checkKind env c k1 k2 =
adamc@3 128 unifyKinds k1 k2
adamc@3 129 handle KUnify (k1, k2, err) =>
adamc@5 130 conError env (WrongKind (c, k1, k2, err))
adamc@3 131
adamc@3 132 val dummy = ErrorMsg.dummySpan
adamc@3 133
adamc@3 134 val ktype = (L'.KType, dummy)
adamc@3 135 val kname = (L'.KName, dummy)
adamc@12 136 val ktype_record = (L'.KRecord ktype, dummy)
adamc@3 137
adamc@3 138 val cerror = (L'.CError, dummy)
adamc@3 139 val kerror = (L'.KError, dummy)
adamc@10 140 val eerror = (L'.EError, dummy)
adamc@31 141 val sgnerror = (L'.SgnError, dummy)
adamc@31 142 val strerror = (L'.StrError, dummy)
adamc@3 143
adamc@3 144 local
adamc@3 145 val count = ref 0
adamc@3 146 in
adamc@3 147
adamc@3 148 fun resetKunif () = count := 0
adamc@3 149
adamc@3 150 fun kunif () =
adamc@3 151 let
adamc@3 152 val n = !count
adamc@3 153 val s = if n <= 26 then
adamc@3 154 str (chr (ord #"A" + n))
adamc@3 155 else
adamc@3 156 "U" ^ Int.toString (n - 26)
adamc@3 157 in
adamc@3 158 count := n + 1;
adamc@3 159 (L'.KUnif (s, ref NONE), dummy)
adamc@3 160 end
adamc@3 161
adamc@3 162 end
adamc@3 163
adamc@10 164 local
adamc@10 165 val count = ref 0
adamc@10 166 in
adamc@10 167
adamc@10 168 fun resetCunif () = count := 0
adamc@10 169
adamc@10 170 fun cunif k =
adamc@10 171 let
adamc@10 172 val n = !count
adamc@10 173 val s = if n <= 26 then
adamc@10 174 str (chr (ord #"A" + n))
adamc@10 175 else
adamc@10 176 "U" ^ Int.toString (n - 26)
adamc@10 177 in
adamc@10 178 count := n + 1;
adamc@10 179 (L'.CUnif (k, s, ref NONE), dummy)
adamc@10 180 end
adamc@10 181
adamc@10 182 end
adamc@10 183
adamc@18 184 fun elabKind (k, loc) =
adamc@18 185 case k of
adamc@18 186 L.KType => (L'.KType, loc)
adamc@18 187 | L.KArrow (k1, k2) => (L'.KArrow (elabKind k1, elabKind k2), loc)
adamc@18 188 | L.KName => (L'.KName, loc)
adamc@18 189 | L.KRecord k => (L'.KRecord (elabKind k), loc)
adamc@18 190 | L.KWild => kunif ()
adamc@18 191
adamc@3 192 fun elabCon env (c, loc) =
adamc@3 193 case c of
adamc@3 194 L.CAnnot (c, k) =>
adamc@3 195 let
adamc@3 196 val k' = elabKind k
adamc@3 197 val (c', ck) = elabCon env c
adamc@3 198 in
adamc@5 199 checkKind env c' ck k';
adamc@3 200 (c', k')
adamc@3 201 end
adamc@3 202
adamc@3 203 | L.TFun (t1, t2) =>
adamc@3 204 let
adamc@3 205 val (t1', k1) = elabCon env t1
adamc@3 206 val (t2', k2) = elabCon env t2
adamc@3 207 in
adamc@5 208 checkKind env t1' k1 ktype;
adamc@5 209 checkKind env t2' k2 ktype;
adamc@3 210 ((L'.TFun (t1', t2'), loc), ktype)
adamc@3 211 end
adamc@3 212 | L.TCFun (e, x, k, t) =>
adamc@3 213 let
adamc@3 214 val e' = elabExplicitness e
adamc@3 215 val k' = elabKind k
adamc@3 216 val env' = E.pushCRel env x k'
adamc@3 217 val (t', tk) = elabCon env' t
adamc@3 218 in
adamc@5 219 checkKind env t' tk ktype;
adamc@3 220 ((L'.TCFun (e', x, k', t'), loc), ktype)
adamc@3 221 end
adamc@3 222 | L.TRecord c =>
adamc@3 223 let
adamc@3 224 val (c', ck) = elabCon env c
adamc@3 225 val k = (L'.KRecord ktype, loc)
adamc@3 226 in
adamc@5 227 checkKind env c' ck k;
adamc@3 228 ((L'.TRecord c', loc), ktype)
adamc@3 229 end
adamc@3 230
adamc@34 231 | L.CVar ([], s) =>
adamc@3 232 (case E.lookupC env s of
adamc@9 233 E.NotBound =>
adamc@5 234 (conError env (UnboundCon (loc, s));
adamc@3 235 (cerror, kerror))
adamc@9 236 | E.Rel (n, k) =>
adamc@3 237 ((L'.CRel n, loc), k)
adamc@9 238 | E.Named (n, k) =>
adamc@3 239 ((L'.CNamed n, loc), k))
adamc@34 240 | L.CVar (m1 :: ms, s) =>
adamc@34 241 (case E.lookupStr env m1 of
adamc@42 242 NONE => (conError env (UnboundStrInCon (loc, m1));
adamc@34 243 (cerror, kerror))
adamc@34 244 | SOME (n, sgn) =>
adamc@34 245 let
adamc@34 246 val (str, sgn) = foldl (fn (m, (str, sgn)) =>
adamc@34 247 case E.projectStr env {sgn = sgn, str = str, field = m} of
adamc@34 248 NONE => (conError env (UnboundStrInCon (loc, m));
adamc@34 249 (strerror, sgnerror))
adamc@34 250 | SOME sgn => ((L'.StrProj (str, m), loc), sgn))
adamc@34 251 ((L'.StrVar n, loc), sgn) ms
adamc@34 252
adamc@34 253 val k = case E.projectCon env {sgn = sgn, str = str, field = s} of
adamc@34 254 NONE => (conError env (UnboundCon (loc, s));
adamc@34 255 kerror)
adamc@34 256 | SOME (k, _) => k
adamc@34 257 in
adamc@34 258 ((L'.CModProj (n, ms, s), loc), k)
adamc@34 259 end)
adamc@34 260
adamc@3 261 | L.CApp (c1, c2) =>
adamc@3 262 let
adamc@3 263 val (c1', k1) = elabCon env c1
adamc@3 264 val (c2', k2) = elabCon env c2
adamc@3 265 val dom = kunif ()
adamc@3 266 val ran = kunif ()
adamc@3 267 in
adamc@5 268 checkKind env c1' k1 (L'.KArrow (dom, ran), loc);
adamc@5 269 checkKind env c2' k2 dom;
adamc@3 270 ((L'.CApp (c1', c2'), loc), ran)
adamc@3 271 end
adamc@8 272 | L.CAbs (x, k, t) =>
adamc@3 273 let
adamc@3 274 val k' = elabKind k
adamc@3 275 val env' = E.pushCRel env x k'
adamc@3 276 val (t', tk) = elabCon env' t
adamc@3 277 in
adamc@8 278 ((L'.CAbs (x, k', t'), loc),
adamc@3 279 (L'.KArrow (k', tk), loc))
adamc@3 280 end
adamc@3 281
adamc@3 282 | L.CName s =>
adamc@3 283 ((L'.CName s, loc), kname)
adamc@3 284
adamc@3 285 | L.CRecord xcs =>
adamc@3 286 let
adamc@3 287 val k = kunif ()
adamc@3 288
adamc@3 289 val xcs' = map (fn (x, c) =>
adamc@3 290 let
adamc@3 291 val (x', xk) = elabCon env x
adamc@3 292 val (c', ck) = elabCon env c
adamc@3 293 in
adamc@5 294 checkKind env x' xk kname;
adamc@5 295 checkKind env c' ck k;
adamc@3 296 (x', c')
adamc@3 297 end) xcs
adamc@3 298 in
adamc@5 299 ((L'.CRecord (k, xcs'), loc), (L'.KRecord k, loc))
adamc@3 300 end
adamc@3 301 | L.CConcat (c1, c2) =>
adamc@3 302 let
adamc@3 303 val (c1', k1) = elabCon env c1
adamc@3 304 val (c2', k2) = elabCon env c2
adamc@3 305 val ku = kunif ()
adamc@3 306 val k = (L'.KRecord ku, loc)
adamc@3 307 in
adamc@5 308 checkKind env c1' k1 k;
adamc@5 309 checkKind env c2' k2 k;
adamc@3 310 ((L'.CConcat (c1', c2'), loc), k)
adamc@3 311 end
adamc@3 312
adamc@18 313 | L.CWild k =>
adamc@18 314 let
adamc@18 315 val k' = elabKind k
adamc@18 316 in
adamc@18 317 (cunif k', k')
adamc@18 318 end
adamc@18 319
adamc@6 320 fun kunifsRemain k =
adamc@6 321 case k of
adamc@6 322 L'.KUnif (_, ref NONE) => true
adamc@6 323 | _ => false
adamc@10 324 fun cunifsRemain c =
adamc@10 325 case c of
adamc@10 326 L'.CUnif (_, _, ref NONE) => true
adamc@10 327 | _ => false
adamc@6 328
adamc@6 329 val kunifsInKind = U.Kind.exists kunifsRemain
adamc@6 330 val kunifsInCon = U.Con.exists {kind = kunifsRemain,
adamc@6 331 con = fn _ => false}
adamc@10 332 val kunifsInExp = U.Exp.exists {kind = kunifsRemain,
adamc@10 333 con = fn _ => false,
adamc@10 334 exp = fn _ => false}
adamc@10 335
adamc@10 336 val cunifsInCon = U.Con.exists {kind = fn _ => false,
adamc@10 337 con = cunifsRemain}
adamc@10 338 val cunifsInExp = U.Exp.exists {kind = fn _ => false,
adamc@10 339 con = cunifsRemain,
adamc@10 340 exp = fn _ => false}
adamc@10 341
adamc@10 342 fun occursCon r =
adamc@10 343 U.Con.exists {kind = fn _ => false,
adamc@10 344 con = fn L'.CUnif (_, _, r') => r = r'
adamc@10 345 | _ => false}
adamc@10 346
adamc@10 347 datatype cunify_error =
adamc@10 348 CKind of L'.kind * L'.kind * kunify_error
adamc@10 349 | COccursCheckFailed of L'.con * L'.con
adamc@10 350 | CIncompatible of L'.con * L'.con
adamc@10 351 | CExplicitness of L'.con * L'.con
adamc@12 352 | CKindof of L'.con
adamc@12 353 | CRecordFailure
adamc@10 354
adamc@10 355 exception CUnify' of cunify_error
adamc@10 356
adamc@10 357 fun cunifyError env err =
adamc@10 358 case err of
adamc@10 359 CKind (k1, k2, kerr) =>
adamc@10 360 (eprefaces "Kind unification failure"
adamc@10 361 [("Kind 1", p_kind k1),
adamc@10 362 ("Kind 2", p_kind k2)];
adamc@10 363 kunifyError kerr)
adamc@10 364 | COccursCheckFailed (c1, c2) =>
adamc@10 365 eprefaces "Constructor occurs check failed"
adamc@10 366 [("Con 1", p_con env c1),
adamc@10 367 ("Con 2", p_con env c2)]
adamc@10 368 | CIncompatible (c1, c2) =>
adamc@10 369 eprefaces "Incompatible constructors"
adamc@10 370 [("Con 1", p_con env c1),
adamc@10 371 ("Con 2", p_con env c2)]
adamc@10 372 | CExplicitness (c1, c2) =>
adamc@10 373 eprefaces "Differing constructor function explicitness"
adamc@10 374 [("Con 1", p_con env c1),
adamc@10 375 ("Con 2", p_con env c2)]
adamc@12 376 | CKindof c =>
adamc@12 377 eprefaces "Kind unification variable blocks kindof calculation"
adamc@12 378 [("Con", p_con env c)]
adamc@12 379 | CRecordFailure =>
adamc@12 380 eprefaces "Can't unify record constructors" []
adamc@10 381
adamc@13 382 exception SynUnif = E.SynUnif
adamc@13 383 val liftConInCon = E.liftConInCon
adamc@12 384
adamc@12 385 val subConInCon =
adamc@12 386 U.Con.mapB {kind = fn k => k,
adamc@12 387 con = fn (xn, rep) => fn c =>
adamc@12 388 case c of
adamc@12 389 L'.CRel xn' =>
adamc@12 390 if xn = xn' then
adamc@12 391 #1 rep
adamc@12 392 else
adamc@12 393 c
adamc@17 394 (*| L'.CUnif _ => raise SynUnif*)
adamc@12 395 | _ => c,
adamc@12 396 bind = fn ((xn, rep), U.Con.Rel _) => (xn+1, liftConInCon 0 rep)
adamc@12 397 | (ctx, _) => ctx}
adamc@12 398
adamc@12 399 type record_summary = {
adamc@12 400 fields : (L'.con * L'.con) list,
adamc@12 401 unifs : (L'.con * L'.con option ref) list,
adamc@12 402 others : L'.con list
adamc@12 403 }
adamc@12 404
adamc@12 405 fun summaryToCon {fields, unifs, others} =
adamc@12 406 let
adamc@12 407 val c = (L'.CRecord (ktype, []), dummy)
adamc@12 408 val c = List.foldr (fn (c', c) => (L'.CConcat (c', c), dummy)) c others
adamc@12 409 val c = List.foldr (fn ((c', _), c) => (L'.CConcat (c', c), dummy)) c unifs
adamc@12 410 in
adamc@12 411 (L'.CConcat ((L'.CRecord (ktype, fields), dummy), c), dummy)
adamc@12 412 end
adamc@12 413
adamc@12 414 fun p_summary env s = p_con env (summaryToCon s)
adamc@12 415
adamc@12 416 exception CUnify of L'.con * L'.con * cunify_error
adamc@12 417
adamc@12 418 fun hnormKind (kAll as (k, _)) =
adamc@12 419 case k of
adamc@12 420 L'.KUnif (_, ref (SOME k)) => hnormKind k
adamc@12 421 | _ => kAll
adamc@12 422
adamc@12 423 fun kindof env (c, loc) =
adamc@12 424 case c of
adamc@12 425 L'.TFun _ => ktype
adamc@12 426 | L'.TCFun _ => ktype
adamc@12 427 | L'.TRecord _ => ktype
adamc@12 428
adamc@12 429 | L'.CRel xn => #2 (E.lookupCRel env xn)
adamc@12 430 | L'.CNamed xn => #2 (E.lookupCNamed env xn)
adamc@34 431 | L'.CModProj (n, ms, x) =>
adamc@34 432 let
adamc@34 433 val (_, sgn) = E.lookupStrNamed env n
adamc@34 434 val (str, sgn) = foldl (fn (m, (str, sgn)) =>
adamc@34 435 case E.projectStr env {sgn = sgn, str = str, field = m} of
adamc@34 436 NONE => raise Fail "kindof: Unknown substructure"
adamc@34 437 | SOME sgn => ((L'.StrProj (str, m), loc), sgn))
adamc@34 438 ((L'.StrVar n, loc), sgn) ms
adamc@34 439 in
adamc@34 440 case E.projectCon env {sgn = sgn, str = str, field = x} of
adamc@34 441 NONE => raise Fail "kindof: Unknown con in structure"
adamc@34 442 | SOME (k, _) => k
adamc@34 443 end
adamc@34 444
adamc@12 445 | L'.CApp (c, _) =>
adamc@12 446 (case #1 (hnormKind (kindof env c)) of
adamc@12 447 L'.KArrow (_, k) => k
adamc@12 448 | L'.KError => kerror
adamc@12 449 | _ => raise CUnify' (CKindof c))
adamc@12 450 | L'.CAbs (x, k, c) => (L'.KArrow (k, kindof (E.pushCRel env x k) c), loc)
adamc@12 451
adamc@12 452 | L'.CName _ => kname
adamc@12 453
adamc@12 454 | L'.CRecord (k, _) => (L'.KRecord k, loc)
adamc@12 455 | L'.CConcat (c, _) => kindof env c
adamc@12 456
adamc@12 457 | L'.CError => kerror
adamc@12 458 | L'.CUnif (k, _, _) => k
adamc@12 459
adamc@12 460 fun unifyRecordCons env (c1, c2) =
adamc@12 461 let
adamc@12 462 val k1 = kindof env c1
adamc@12 463 val k2 = kindof env c2
adamc@12 464 in
adamc@12 465 unifyKinds k1 k2;
adamc@12 466 unifySummaries env (k1, recordSummary env c1, recordSummary env c2)
adamc@12 467 end
adamc@12 468
adamc@12 469 and recordSummary env c : record_summary =
adamc@12 470 case hnormCon env c of
adamc@12 471 (L'.CRecord (_, xcs), _) => {fields = xcs, unifs = [], others = []}
adamc@12 472 | (L'.CConcat (c1, c2), _) =>
adamc@12 473 let
adamc@12 474 val s1 = recordSummary env c1
adamc@12 475 val s2 = recordSummary env c2
adamc@12 476 in
adamc@12 477 {fields = #fields s1 @ #fields s2,
adamc@12 478 unifs = #unifs s1 @ #unifs s2,
adamc@12 479 others = #others s1 @ #others s2}
adamc@12 480 end
adamc@12 481 | (L'.CUnif (_, _, ref (SOME c)), _) => recordSummary env c
adamc@12 482 | c' as (L'.CUnif (_, _, r), _) => {fields = [], unifs = [(c', r)], others = []}
adamc@12 483 | c' => {fields = [], unifs = [], others = [c']}
adamc@12 484
adamc@12 485 and consEq env (c1, c2) =
adamc@12 486 (unifyCons env c1 c2;
adamc@12 487 true)
adamc@12 488 handle CUnify _ => false
adamc@12 489
adamc@12 490 and unifySummaries env (k, s1 : record_summary, s2 : record_summary) =
adamc@12 491 let
adamc@14 492 (*val () = eprefaces "Summaries" [("#1", p_summary env s1),
adamc@14 493 ("#2", p_summary env s2)]*)
adamc@12 494
adamc@12 495 fun eatMatching p (ls1, ls2) =
adamc@12 496 let
adamc@12 497 fun em (ls1, ls2, passed1) =
adamc@12 498 case ls1 of
adamc@12 499 [] => (rev passed1, ls2)
adamc@12 500 | h1 :: t1 =>
adamc@12 501 let
adamc@12 502 fun search (ls2', passed2) =
adamc@12 503 case ls2' of
adamc@12 504 [] => em (t1, ls2, h1 :: passed1)
adamc@12 505 | h2 :: t2 =>
adamc@12 506 if p (h1, h2) then
adamc@12 507 em (t1, List.revAppend (passed2, t2), passed1)
adamc@12 508 else
adamc@12 509 search (t2, h2 :: passed2)
adamc@12 510 in
adamc@12 511 search (ls2, [])
adamc@12 512 end
adamc@12 513 in
adamc@12 514 em (ls1, ls2, [])
adamc@12 515 end
adamc@12 516
adamc@12 517 val (fs1, fs2) = eatMatching (fn ((x1, c1), (x2, c2)) =>
adamc@12 518 if consEq env (x1, x2) then
adamc@12 519 (unifyCons env c1 c2;
adamc@12 520 true)
adamc@12 521 else
adamc@12 522 false) (#fields s1, #fields s2)
adamc@14 523 (*val () = eprefaces "Summaries2" [("#1", p_summary env {fields = fs1, unifs = #unifs s1, others = #others s1}),
adamc@14 524 ("#2", p_summary env {fields = fs2, unifs = #unifs s2, others = #others s2})]*)
adamc@12 525 val (unifs1, unifs2) = eatMatching (fn ((_, r1), (_, r2)) => r1 = r2) (#unifs s1, #unifs s2)
adamc@12 526 val (others1, others2) = eatMatching (consEq env) (#others s1, #others s2)
adamc@12 527
adamc@12 528 fun unifFields (fs, others, unifs) =
adamc@12 529 case (fs, others, unifs) of
adamc@12 530 ([], [], _) => ([], [], unifs)
adamc@12 531 | (_, _, []) => (fs, others, [])
adamc@12 532 | (_, _, (_, r) :: rest) =>
adamc@12 533 let
adamc@12 534 val r' = ref NONE
adamc@12 535 val cr' = (L'.CUnif (k, "recd", r'), dummy)
adamc@12 536
adamc@12 537 val prefix = case (fs, others) of
adamc@12 538 ([], other :: others) =>
adamc@12 539 List.foldl (fn (other, c) =>
adamc@12 540 (L'.CConcat (c, other), dummy))
adamc@12 541 other others
adamc@12 542 | (fs, []) =>
adamc@12 543 (L'.CRecord (k, fs), dummy)
adamc@12 544 | (fs, others) =>
adamc@12 545 List.foldl (fn (other, c) =>
adamc@12 546 (L'.CConcat (c, other), dummy))
adamc@12 547 (L'.CRecord (k, fs), dummy) others
adamc@12 548 in
adamc@12 549 r := SOME (L'.CConcat (prefix, cr'), dummy);
adamc@12 550 ([], [], (cr', r') :: rest)
adamc@12 551 end
adamc@12 552
adamc@12 553 val (fs1, others1, unifs2) = unifFields (fs1, others1, unifs2)
adamc@12 554 val (fs2, others2, unifs1) = unifFields (fs2, others2, unifs1)
adamc@12 555
adamc@12 556 val clear1 = case (fs1, others1) of
adamc@12 557 ([], []) => true
adamc@12 558 | _ => false
adamc@12 559 val clear2 = case (fs2, others2) of
adamc@12 560 ([], []) => true
adamc@12 561 | _ => false
adamc@12 562 val empty = (L'.CRecord (k, []), dummy)
adamc@12 563 fun pairOffUnifs (unifs1, unifs2) =
adamc@12 564 case (unifs1, unifs2) of
adamc@12 565 ([], _) =>
adamc@12 566 if clear1 then
adamc@12 567 List.app (fn (_, r) => r := SOME empty) unifs2
adamc@12 568 else
adamc@12 569 raise CUnify' CRecordFailure
adamc@12 570 | (_, []) =>
adamc@12 571 if clear2 then
adamc@12 572 List.app (fn (_, r) => r := SOME empty) unifs1
adamc@12 573 else
adamc@12 574 raise CUnify' CRecordFailure
adamc@12 575 | ((c1, _) :: rest1, (_, r2) :: rest2) =>
adamc@12 576 (r2 := SOME c1;
adamc@12 577 pairOffUnifs (rest1, rest2))
adamc@12 578 in
adamc@12 579 pairOffUnifs (unifs1, unifs2)
adamc@12 580 end
adamc@12 581
adamc@34 582 and hnormCon env (cAll as (c, loc)) =
adamc@11 583 case c of
adamc@11 584 L'.CUnif (_, _, ref (SOME c)) => hnormCon env c
adamc@11 585
adamc@11 586 | L'.CNamed xn =>
adamc@11 587 (case E.lookupCNamed env xn of
adamc@11 588 (_, _, SOME c') => hnormCon env c'
adamc@11 589 | _ => cAll)
adamc@11 590
adamc@34 591 | L'.CModProj (n, ms, x) =>
adamc@34 592 let
adamc@34 593 val (_, sgn) = E.lookupStrNamed env n
adamc@34 594 val (str, sgn) = foldl (fn (m, (str, sgn)) =>
adamc@34 595 case E.projectStr env {sgn = sgn, str = str, field = m} of
adamc@34 596 NONE => raise Fail "hnormCon: Unknown substructure"
adamc@34 597 | SOME sgn => ((L'.StrProj (str, m), loc), sgn))
adamc@34 598 ((L'.StrVar n, loc), sgn) ms
adamc@34 599 in
adamc@34 600 case E.projectCon env {sgn = sgn, str = str, field = x} of
adamc@34 601 NONE => raise Fail "kindof: Unknown con in structure"
adamc@34 602 | SOME (_, NONE) => cAll
adamc@34 603 | SOME (_, SOME c) => hnormCon env c
adamc@34 604 end
adamc@34 605
adamc@12 606 | L'.CApp (c1, c2) =>
adamc@12 607 (case hnormCon env c1 of
adamc@12 608 (L'.CAbs (_, _, cb), _) =>
adamc@12 609 ((hnormCon env (subConInCon (0, c2) cb))
adamc@12 610 handle SynUnif => cAll)
adamc@12 611 | _ => cAll)
adamc@12 612
adamc@12 613 | L'.CConcat (c1, c2) =>
adamc@12 614 (case (hnormCon env c1, hnormCon env c2) of
adamc@12 615 ((L'.CRecord (k, xcs1), loc), (L'.CRecord (_, xcs2), _)) =>
adamc@12 616 (L'.CRecord (k, xcs1 @ xcs2), loc)
adamc@12 617 | _ => cAll)
adamc@12 618
adamc@11 619 | _ => cAll
adamc@11 620
adamc@12 621 and unifyCons' env c1 c2 =
adamc@11 622 unifyCons'' env (hnormCon env c1) (hnormCon env c2)
adamc@11 623
adamc@11 624 and unifyCons'' env (c1All as (c1, _)) (c2All as (c2, _)) =
adamc@10 625 let
adamc@10 626 fun err f = raise CUnify' (f (c1All, c2All))
adamc@12 627
adamc@12 628 fun isRecord () = unifyRecordCons env (c1All, c2All)
adamc@10 629 in
adamc@10 630 case (c1, c2) of
adamc@10 631 (L'.TFun (d1, r1), L'.TFun (d2, r2)) =>
adamc@10 632 (unifyCons' env d1 d2;
adamc@10 633 unifyCons' env r1 r2)
adamc@10 634 | (L'.TCFun (expl1, x1, d1, r1), L'.TCFun (expl2, _, d2, r2)) =>
adamc@10 635 if expl1 <> expl2 then
adamc@10 636 err CExplicitness
adamc@10 637 else
adamc@10 638 (unifyKinds d1 d2;
adamc@10 639 unifyCons' (E.pushCRel env x1 d1) r1 r2)
adamc@10 640 | (L'.TRecord r1, L'.TRecord r2) => unifyCons' env r1 r2
adamc@10 641
adamc@10 642 | (L'.CRel n1, L'.CRel n2) =>
adamc@10 643 if n1 = n2 then
adamc@10 644 ()
adamc@10 645 else
adamc@10 646 err CIncompatible
adamc@10 647 | (L'.CNamed n1, L'.CNamed n2) =>
adamc@10 648 if n1 = n2 then
adamc@10 649 ()
adamc@10 650 else
adamc@10 651 err CIncompatible
adamc@10 652
adamc@10 653 | (L'.CApp (d1, r1), L'.CApp (d2, r2)) =>
adamc@10 654 (unifyCons' env d1 d2;
adamc@10 655 unifyCons' env r1 r2)
adamc@10 656 | (L'.CAbs (x1, k1, c1), L'.CAbs (_, k2, c2)) =>
adamc@10 657 (unifyKinds k1 k2;
adamc@10 658 unifyCons' (E.pushCRel env x1 k1) c1 c2)
adamc@10 659
adamc@10 660 | (L'.CName n1, L'.CName n2) =>
adamc@10 661 if n1 = n2 then
adamc@10 662 ()
adamc@10 663 else
adamc@10 664 err CIncompatible
adamc@10 665
adamc@34 666 | (L'.CModProj (n1, ms1, x1), L'.CModProj (n2, ms2, x2)) =>
adamc@34 667 if n1 = n2 andalso ms1 = ms2 andalso x1 = x2 then
adamc@34 668 ()
adamc@34 669 else
adamc@34 670 err CIncompatible
adamc@34 671
adamc@10 672 | (L'.CError, _) => ()
adamc@10 673 | (_, L'.CError) => ()
adamc@10 674
adamc@10 675 | (L'.CUnif (_, _, ref (SOME c1All)), _) => unifyCons' env c1All c2All
adamc@10 676 | (_, L'.CUnif (_, _, ref (SOME c2All))) => unifyCons' env c1All c2All
adamc@10 677
adamc@10 678 | (L'.CUnif (k1, _, r1), L'.CUnif (k2, _, r2)) =>
adamc@10 679 if r1 = r2 then
adamc@10 680 ()
adamc@10 681 else
adamc@10 682 (unifyKinds k1 k2;
adamc@10 683 r1 := SOME c2All)
adamc@10 684
adamc@10 685 | (L'.CUnif (_, _, r), _) =>
adamc@10 686 if occursCon r c2All then
adamc@10 687 err COccursCheckFailed
adamc@10 688 else
adamc@10 689 r := SOME c2All
adamc@10 690 | (_, L'.CUnif (_, _, r)) =>
adamc@10 691 if occursCon r c1All then
adamc@10 692 err COccursCheckFailed
adamc@10 693 else
adamc@10 694 r := SOME c1All
adamc@10 695
adamc@12 696 | (L'.CRecord _, _) => isRecord ()
adamc@12 697 | (_, L'.CRecord _) => isRecord ()
adamc@12 698 | (L'.CConcat _, _) => isRecord ()
adamc@12 699 | (_, L'.CConcat _) => isRecord ()
adamc@12 700
adamc@10 701 | _ => err CIncompatible
adamc@10 702 end
adamc@10 703
adamc@12 704 and unifyCons env c1 c2 =
adamc@10 705 unifyCons' env c1 c2
adamc@10 706 handle CUnify' err => raise CUnify (c1, c2, err)
adamc@10 707 | KUnify args => raise CUnify (c1, c2, CKind args)
adamc@10 708
adamc@10 709 datatype exp_error =
adamc@10 710 UnboundExp of ErrorMsg.span * string
adamc@34 711 | UnboundStrInExp of ErrorMsg.span * string
adamc@10 712 | Unify of L'.exp * L'.con * L'.con * cunify_error
adamc@11 713 | Unif of string * L'.con
adamc@11 714 | WrongForm of string * L'.exp * L'.con
adamc@10 715
adamc@10 716 fun expError env err =
adamc@10 717 case err of
adamc@10 718 UnboundExp (loc, s) =>
adamc@10 719 ErrorMsg.errorAt loc ("Unbound expression variable " ^ s)
adamc@34 720 | UnboundStrInExp (loc, s) =>
adamc@34 721 ErrorMsg.errorAt loc ("Unbound structure " ^ s)
adamc@10 722 | Unify (e, c1, c2, uerr) =>
adamc@10 723 (ErrorMsg.errorAt (#2 e) "Unification failure";
adamc@10 724 eprefaces' [("Expression", p_exp env e),
adamc@10 725 ("Have con", p_con env c1),
adamc@10 726 ("Need con", p_con env c2)];
adamc@10 727 cunifyError env uerr)
adamc@11 728 | Unif (action, c) =>
adamc@11 729 (ErrorMsg.errorAt (#2 c) ("Unification variable blocks " ^ action);
adamc@11 730 eprefaces' [("Con", p_con env c)])
adamc@11 731 | WrongForm (variety, e, t) =>
adamc@11 732 (ErrorMsg.errorAt (#2 e) ("Expression is not a " ^ variety);
adamc@11 733 eprefaces' [("Expression", p_exp env e),
adamc@11 734 ("Type", p_con env t)])
adamc@10 735
adamc@10 736 fun checkCon env e c1 c2 =
adamc@10 737 unifyCons env c1 c2
adamc@10 738 handle CUnify (c1, c2, err) =>
adamc@10 739 expError env (Unify (e, c1, c2, err))
adamc@10 740
adamc@14 741 fun primType env p =
adamc@14 742 let
adamc@14 743 val s = case p of
adamc@14 744 P.Int _ => "int"
adamc@14 745 | P.Float _ => "float"
adamc@14 746 | P.String _ => "string"
adamc@14 747 in
adamc@14 748 case E.lookupC env s of
adamc@14 749 E.NotBound => raise Fail ("Primitive type " ^ s ^ " unbound")
adamc@14 750 | E.Rel _ => raise Fail ("Primitive type " ^ s ^ " bound as relative")
adamc@14 751 | E.Named (n, (L'.KType, _)) => L'.CNamed n
adamc@14 752 | E.Named _ => raise Fail ("Primitive type " ^ s ^ " bound at non-Type kind")
adamc@14 753 end
adamc@14 754
adamc@15 755 fun typeof env (e, loc) =
adamc@15 756 case e of
adamc@15 757 L'.EPrim p => (primType env p, loc)
adamc@15 758 | L'.ERel n => #2 (E.lookupERel env n)
adamc@15 759 | L'.ENamed n => #2 (E.lookupENamed env n)
adamc@34 760 | L'.EModProj (n, ms, x) =>
adamc@34 761 let
adamc@34 762 val (_, sgn) = E.lookupStrNamed env n
adamc@34 763 val (str, sgn) = foldl (fn (m, (str, sgn)) =>
adamc@34 764 case E.projectStr env {sgn = sgn, str = str, field = m} of
adamc@34 765 NONE => raise Fail "kindof: Unknown substructure"
adamc@34 766 | SOME sgn => ((L'.StrProj (str, m), loc), sgn))
adamc@34 767 ((L'.StrVar n, loc), sgn) ms
adamc@34 768 in
adamc@34 769 case E.projectVal env {sgn = sgn, str = str, field = x} of
adamc@34 770 NONE => raise Fail "typeof: Unknown val in structure"
adamc@34 771 | SOME t => t
adamc@34 772 end
adamc@34 773
adamc@15 774 | L'.EApp (e1, _) =>
adamc@15 775 (case #1 (typeof env e1) of
adamc@15 776 L'.TFun (_, c) => c
adamc@15 777 | _ => raise Fail "typeof: Bad EApp")
adamc@26 778 | L'.EAbs (_, _, ran, _) => ran
adamc@15 779 | L'.ECApp (e1, c) =>
adamc@15 780 (case #1 (typeof env e1) of
adamc@15 781 L'.TCFun (_, _, _, c1) => subConInCon (0, c) c1
adamc@15 782 | _ => raise Fail "typeof: Bad ECApp")
adamc@15 783 | L'.ECAbs (expl, x, k, e1) => (L'.TCFun (expl, x, k, typeof (E.pushCRel env x k) e1), loc)
adamc@15 784
adamc@29 785 | L'.ERecord xes => (L'.TRecord (L'.CRecord (ktype, map (fn (x, _, t) => (x, t)) xes), loc), loc)
adamc@15 786 | L'.EField (_, _, {field, ...}) => field
adamc@15 787
adamc@15 788 | L'.EError => cerror
adamc@15 789
adamc@15 790 fun elabHead env (e as (_, loc)) t =
adamc@15 791 let
adamc@15 792 fun unravel (t, e) =
adamc@15 793 case hnormCon env t of
adamc@15 794 (L'.TCFun (L'.Implicit, x, k, t'), _) =>
adamc@15 795 let
adamc@15 796 val u = cunif k
adamc@15 797 in
adamc@15 798 unravel (subConInCon (0, u) t',
adamc@15 799 (L'.ECApp (e, u), loc))
adamc@15 800 end
adamc@15 801 | _ => (e, t)
adamc@15 802 in
adamc@15 803 unravel (t, e)
adamc@15 804 end
adamc@15 805
adamc@10 806 fun elabExp env (e, loc) =
adamc@10 807 case e of
adamc@10 808 L.EAnnot (e, t) =>
adamc@10 809 let
adamc@10 810 val (e', et) = elabExp env e
adamc@10 811 val (t', _) = elabCon env t
adamc@10 812 in
adamc@10 813 checkCon env e' et t';
adamc@10 814 (e', t')
adamc@10 815 end
adamc@10 816
adamc@14 817 | L.EPrim p => ((L'.EPrim p, loc), (primType env p, loc))
adamc@34 818 | L.EVar ([], s) =>
adamc@10 819 (case E.lookupE env s of
adamc@10 820 E.NotBound =>
adamc@10 821 (expError env (UnboundExp (loc, s));
adamc@10 822 (eerror, cerror))
adamc@10 823 | E.Rel (n, t) => ((L'.ERel n, loc), t)
adamc@10 824 | E.Named (n, t) => ((L'.ENamed n, loc), t))
adamc@34 825 | L.EVar (m1 :: ms, s) =>
adamc@34 826 (case E.lookupStr env m1 of
adamc@42 827 NONE => (expError env (UnboundStrInExp (loc, m1));
adamc@34 828 (eerror, cerror))
adamc@34 829 | SOME (n, sgn) =>
adamc@34 830 let
adamc@34 831 val (str, sgn) = foldl (fn (m, (str, sgn)) =>
adamc@34 832 case E.projectStr env {sgn = sgn, str = str, field = m} of
adamc@34 833 NONE => (conError env (UnboundStrInCon (loc, m));
adamc@34 834 (strerror, sgnerror))
adamc@34 835 | SOME sgn => ((L'.StrProj (str, m), loc), sgn))
adamc@34 836 ((L'.StrVar n, loc), sgn) ms
adamc@34 837
adamc@34 838 val t = case E.projectVal env {sgn = sgn, str = str, field = s} of
adamc@34 839 NONE => (expError env (UnboundExp (loc, s));
adamc@34 840 cerror)
adamc@34 841 | SOME t => t
adamc@34 842 in
adamc@34 843 ((L'.EModProj (n, ms, s), loc), t)
adamc@34 844 end)
adamc@34 845
adamc@10 846 | L.EApp (e1, e2) =>
adamc@10 847 let
adamc@10 848 val (e1', t1) = elabExp env e1
adamc@15 849 val (e1', t1) = elabHead env e1' t1
adamc@10 850 val (e2', t2) = elabExp env e2
adamc@10 851
adamc@10 852 val dom = cunif ktype
adamc@10 853 val ran = cunif ktype
adamc@10 854 val t = (L'.TFun (dom, ran), dummy)
adamc@10 855 in
adamc@10 856 checkCon env e1' t1 t;
adamc@10 857 checkCon env e2' t2 dom;
adamc@10 858 ((L'.EApp (e1', e2'), loc), ran)
adamc@10 859 end
adamc@10 860 | L.EAbs (x, to, e) =>
adamc@10 861 let
adamc@10 862 val t' = case to of
adamc@10 863 NONE => cunif ktype
adamc@10 864 | SOME t =>
adamc@10 865 let
adamc@10 866 val (t', tk) = elabCon env t
adamc@10 867 in
adamc@10 868 checkKind env t' tk ktype;
adamc@10 869 t'
adamc@10 870 end
adamc@10 871 val (e', et) = elabExp (E.pushERel env x t') e
adamc@10 872 in
adamc@26 873 ((L'.EAbs (x, t', et, e'), loc),
adamc@10 874 (L'.TFun (t', et), loc))
adamc@10 875 end
adamc@10 876 | L.ECApp (e, c) =>
adamc@10 877 let
adamc@10 878 val (e', et) = elabExp env e
adamc@15 879 val (e', et) = elabHead env e' et
adamc@10 880 val (c', ck) = elabCon env c
adamc@10 881 in
adamc@11 882 case #1 (hnormCon env et) of
adamc@11 883 L'.CError => (eerror, cerror)
adamc@11 884 | L'.TCFun (_, _, k, eb) =>
adamc@11 885 let
adamc@11 886 val () = checkKind env c' ck k
adamc@11 887 val eb' = subConInCon (0, c') eb
adamc@11 888 handle SynUnif => (expError env (Unif ("substitution", eb));
adamc@11 889 cerror)
adamc@11 890 in
adamc@11 891 ((L'.ECApp (e', c'), loc), eb')
adamc@11 892 end
adamc@11 893
adamc@11 894 | L'.CUnif _ =>
adamc@11 895 (expError env (Unif ("application", et));
adamc@11 896 (eerror, cerror))
adamc@11 897
adamc@11 898 | _ =>
adamc@11 899 (expError env (WrongForm ("constructor function", e', et));
adamc@11 900 (eerror, cerror))
adamc@10 901 end
adamc@11 902 | L.ECAbs (expl, x, k, e) =>
adamc@11 903 let
adamc@11 904 val expl' = elabExplicitness expl
adamc@11 905 val k' = elabKind k
adamc@11 906 val (e', et) = elabExp (E.pushCRel env x k') e
adamc@11 907 in
adamc@11 908 ((L'.ECAbs (expl', x, k', e'), loc),
adamc@11 909 (L'.TCFun (expl', x, k', et), loc))
adamc@11 910 end
adamc@6 911
adamc@12 912 | L.ERecord xes =>
adamc@12 913 let
adamc@12 914 val xes' = map (fn (x, e) =>
adamc@12 915 let
adamc@12 916 val (x', xk) = elabCon env x
adamc@12 917 val (e', et) = elabExp env e
adamc@12 918 in
adamc@12 919 checkKind env x' xk kname;
adamc@12 920 (x', e', et)
adamc@12 921 end) xes
adamc@12 922 in
adamc@29 923 ((L'.ERecord xes', loc),
adamc@12 924 (L'.TRecord (L'.CRecord (ktype, map (fn (x', _, et) => (x', et)) xes'), loc), loc))
adamc@12 925 end
adamc@12 926
adamc@12 927 | L.EField (e, c) =>
adamc@12 928 let
adamc@12 929 val (e', et) = elabExp env e
adamc@12 930 val (c', ck) = elabCon env c
adamc@12 931
adamc@12 932 val ft = cunif ktype
adamc@12 933 val rest = cunif ktype_record
adamc@12 934 in
adamc@12 935 checkKind env c' ck kname;
adamc@12 936 checkCon env e' et (L'.TRecord (L'.CConcat ((L'.CRecord (ktype, [(c', ft)]), loc), rest), loc), loc);
adamc@12 937 ((L'.EField (e', c', {field = ft, rest = rest}), loc), ft)
adamc@12 938 end
adamc@12 939
adamc@12 940
adamc@6 941 datatype decl_error =
adamc@6 942 KunifsRemainKind of ErrorMsg.span * L'.kind
adamc@6 943 | KunifsRemainCon of ErrorMsg.span * L'.con
adamc@10 944 | KunifsRemainExp of ErrorMsg.span * L'.exp
adamc@10 945 | CunifsRemainCon of ErrorMsg.span * L'.con
adamc@10 946 | CunifsRemainExp of ErrorMsg.span * L'.exp
adamc@6 947
adamc@6 948 fun declError env err =
adamc@6 949 case err of
adamc@6 950 KunifsRemainKind (loc, k) =>
adamc@6 951 (ErrorMsg.errorAt loc "Some kind unification variables are undetermined in kind";
adamc@6 952 eprefaces' [("Kind", p_kind k)])
adamc@6 953 | KunifsRemainCon (loc, c) =>
adamc@6 954 (ErrorMsg.errorAt loc "Some kind unification variables are undetermined in constructor";
adamc@6 955 eprefaces' [("Constructor", p_con env c)])
adamc@10 956 | KunifsRemainExp (loc, e) =>
adamc@10 957 (ErrorMsg.errorAt loc "Some kind unification variables are undetermined in expression";
adamc@10 958 eprefaces' [("Expression", p_exp env e)])
adamc@10 959 | CunifsRemainCon (loc, c) =>
adamc@10 960 (ErrorMsg.errorAt loc "Some constructor unification variables are undetermined in constructor";
adamc@10 961 eprefaces' [("Constructor", p_con env c)])
adamc@10 962 | CunifsRemainExp (loc, e) =>
adamc@10 963 (ErrorMsg.errorAt loc "Some constructor unification variables are undetermined in expression";
adamc@10 964 eprefaces' [("Expression", p_exp env e)])
adamc@6 965
adamc@31 966 datatype sgn_error =
adamc@31 967 UnboundSgn of ErrorMsg.span * string
adamc@31 968 | UnmatchedSgi of L'.sgn_item
adamc@31 969 | SgiWrongKind of L'.sgn_item * L'.kind * L'.sgn_item * L'.kind * kunify_error
adamc@31 970 | SgiWrongCon of L'.sgn_item * L'.con * L'.sgn_item * L'.con * cunify_error
adamc@41 971 | SgnWrongForm of L'.sgn * L'.sgn
adamc@42 972 | UnWhereable of L'.sgn * string
adamc@31 973
adamc@31 974 fun sgnError env err =
adamc@31 975 case err of
adamc@31 976 UnboundSgn (loc, s) =>
adamc@31 977 ErrorMsg.errorAt loc ("Unbound signature variable " ^ s)
adamc@31 978 | UnmatchedSgi (sgi as (_, loc)) =>
adamc@31 979 (ErrorMsg.errorAt loc "Unmatched signature item";
adamc@31 980 eprefaces' [("Item", p_sgn_item env sgi)])
adamc@31 981 | SgiWrongKind (sgi1, k1, sgi2, k2, kerr) =>
adamc@31 982 (ErrorMsg.errorAt (#2 sgi1) "Kind unification failure in signature matching:";
adamc@31 983 eprefaces' [("Item 1", p_sgn_item env sgi1),
adamc@31 984 ("Item 2", p_sgn_item env sgi2),
adamc@31 985 ("Kind 1", p_kind k1),
adamc@31 986 ("Kind 2", p_kind k2)];
adamc@31 987 kunifyError kerr)
adamc@31 988 | SgiWrongCon (sgi1, c1, sgi2, c2, cerr) =>
adamc@31 989 (ErrorMsg.errorAt (#2 sgi1) "Constructor unification failure in signature matching:";
adamc@31 990 eprefaces' [("Item 1", p_sgn_item env sgi1),
adamc@31 991 ("Item 2", p_sgn_item env sgi2),
adamc@31 992 ("Con 1", p_con env c1),
adamc@31 993 ("Con 2", p_con env c2)];
adamc@31 994 cunifyError env cerr)
adamc@41 995 | SgnWrongForm (sgn1, sgn2) =>
adamc@41 996 (ErrorMsg.errorAt (#2 sgn1) "Incompatible signatures:";
adamc@41 997 eprefaces' [("Sig 1", p_sgn env sgn1),
adamc@41 998 ("Sig 2", p_sgn env sgn2)])
adamc@42 999 | UnWhereable (sgn, x) =>
adamc@42 1000 (ErrorMsg.errorAt (#2 sgn) "Unavailable field for 'where'";
adamc@42 1001 eprefaces' [("Signature", p_sgn env sgn),
adamc@42 1002 ("Field", PD.string x)])
adamc@31 1003
adamc@31 1004 datatype str_error =
adamc@31 1005 UnboundStr of ErrorMsg.span * string
adamc@31 1006
adamc@31 1007 fun strError env err =
adamc@31 1008 case err of
adamc@31 1009 UnboundStr (loc, s) =>
adamc@31 1010 ErrorMsg.errorAt loc ("Unbound structure variable " ^ s)
adamc@31 1011
adamc@42 1012 val hnormSgn = E.hnormSgn
adamc@31 1013
adamc@31 1014 fun elabSgn_item ((sgi, loc), env) =
adamc@31 1015 let
adamc@31 1016
adamc@31 1017 in
adamc@31 1018 resetKunif ();
adamc@31 1019 resetCunif ();
adamc@31 1020 case sgi of
adamc@31 1021 L.SgiConAbs (x, k) =>
adamc@31 1022 let
adamc@31 1023 val k' = elabKind k
adamc@31 1024
adamc@31 1025 val (env', n) = E.pushCNamed env x k' NONE
adamc@31 1026 in
adamc@31 1027 if ErrorMsg.anyErrors () then
adamc@31 1028 ()
adamc@31 1029 else (
adamc@31 1030 if kunifsInKind k' then
adamc@31 1031 declError env (KunifsRemainKind (loc, k'))
adamc@31 1032 else
adamc@31 1033 ()
adamc@31 1034 );
adamc@31 1035
adamc@31 1036 ((L'.SgiConAbs (x, n, k'), loc), env')
adamc@31 1037 end
adamc@31 1038
adamc@31 1039 | L.SgiCon (x, ko, c) =>
adamc@31 1040 let
adamc@31 1041 val k' = case ko of
adamc@31 1042 NONE => kunif ()
adamc@31 1043 | SOME k => elabKind k
adamc@31 1044
adamc@31 1045 val (c', ck) = elabCon env c
adamc@31 1046 val (env', n) = E.pushCNamed env x k' (SOME c')
adamc@31 1047 in
adamc@31 1048 checkKind env c' ck k';
adamc@31 1049
adamc@31 1050 if ErrorMsg.anyErrors () then
adamc@31 1051 ()
adamc@31 1052 else (
adamc@31 1053 if kunifsInKind k' then
adamc@31 1054 declError env (KunifsRemainKind (loc, k'))
adamc@31 1055 else
adamc@31 1056 ();
adamc@31 1057
adamc@31 1058 if kunifsInCon c' then
adamc@31 1059 declError env (KunifsRemainCon (loc, c'))
adamc@31 1060 else
adamc@31 1061 ()
adamc@31 1062 );
adamc@31 1063
adamc@31 1064 ((L'.SgiCon (x, n, k', c'), loc), env')
adamc@31 1065 end
adamc@31 1066
adamc@31 1067 | L.SgiVal (x, c) =>
adamc@31 1068 let
adamc@31 1069 val (c', ck) = elabCon env c
adamc@31 1070
adamc@31 1071 val (env', n) = E.pushENamed env x c'
adamc@31 1072 in
adamc@31 1073 unifyKinds ck ktype;
adamc@31 1074
adamc@31 1075 if ErrorMsg.anyErrors () then
adamc@31 1076 ()
adamc@31 1077 else (
adamc@31 1078 if kunifsInCon c' then
adamc@31 1079 declError env (KunifsRemainCon (loc, c'))
adamc@31 1080 else
adamc@31 1081 ()
adamc@31 1082 );
adamc@31 1083
adamc@31 1084 ((L'.SgiVal (x, n, c'), loc), env')
adamc@31 1085 end
adamc@31 1086
adamc@31 1087 | L.SgiStr (x, sgn) =>
adamc@31 1088 let
adamc@31 1089 val sgn' = elabSgn env sgn
adamc@31 1090 val (env', n) = E.pushStrNamed env x sgn'
adamc@31 1091 in
adamc@31 1092 ((L'.SgiStr (x, n, sgn'), loc), env')
adamc@31 1093 end
adamc@31 1094
adamc@31 1095 end
adamc@31 1096
adamc@31 1097 and elabSgn env (sgn, loc) =
adamc@31 1098 case sgn of
adamc@31 1099 L.SgnConst sgis =>
adamc@31 1100 let
adamc@31 1101 val (sgis', _) = ListUtil.foldlMap elabSgn_item env sgis
adamc@31 1102 in
adamc@31 1103 (L'.SgnConst sgis', loc)
adamc@31 1104 end
adamc@31 1105 | L.SgnVar x =>
adamc@31 1106 (case E.lookupSgn env x of
adamc@31 1107 NONE =>
adamc@31 1108 (sgnError env (UnboundSgn (loc, x));
adamc@31 1109 (L'.SgnError, loc))
adamc@31 1110 | SOME (n, sgis) => (L'.SgnVar n, loc))
adamc@41 1111 | L.SgnFun (m, dom, ran) =>
adamc@41 1112 let
adamc@41 1113 val dom' = elabSgn env dom
adamc@41 1114 val (env', n) = E.pushStrNamed env m dom'
adamc@41 1115 val ran' = elabSgn env' ran
adamc@41 1116 in
adamc@41 1117 (L'.SgnFun (m, n, dom', ran'), loc)
adamc@41 1118 end
adamc@42 1119 | L.SgnWhere (sgn, x, c) =>
adamc@42 1120 let
adamc@42 1121 val sgn' = elabSgn env sgn
adamc@42 1122 val (c', ck) = elabCon env c
adamc@42 1123 in
adamc@42 1124 case #1 (hnormSgn env sgn') of
adamc@42 1125 L'.SgnError => sgnerror
adamc@42 1126 | L'.SgnConst sgis =>
adamc@42 1127 if List.exists (fn (L'.SgiConAbs (x, _, k), _) =>
adamc@42 1128 (unifyKinds k ck;
adamc@42 1129 true)
adamc@42 1130 | _ => false) sgis then
adamc@42 1131 (L'.SgnWhere (sgn', x, c'), loc)
adamc@42 1132 else
adamc@42 1133 (sgnError env (UnWhereable (sgn', x));
adamc@42 1134 sgnerror)
adamc@42 1135 | _ => (sgnError env (UnWhereable (sgn', x));
adamc@42 1136 sgnerror)
adamc@42 1137 end
adamc@31 1138
adamc@31 1139 fun sgiOfDecl (d, loc) =
adamc@31 1140 case d of
adamc@31 1141 L'.DCon (x, n, k, c) => SOME (L'.SgiCon (x, n, k, c), loc)
adamc@31 1142 | L'.DVal (x, n, t, _) => SOME (L'.SgiVal (x, n, t), loc)
adamc@31 1143 | L'.DSgn _ => NONE
adamc@31 1144 | L'.DStr (x, n, sgn, _) => SOME (L'.SgiStr (x, n, sgn), loc)
adamc@31 1145
adamc@35 1146 fun subSgn env sgn1 (sgn2 as (_, loc2)) =
adamc@35 1147 case (#1 (hnormSgn env sgn1), #1 (hnormSgn env sgn2)) of
adamc@31 1148 (L'.SgnError, _) => ()
adamc@31 1149 | (_, L'.SgnError) => ()
adamc@31 1150
adamc@31 1151 | (L'.SgnConst sgis1, L'.SgnConst sgis2) =>
adamc@31 1152 let
adamc@31 1153 fun folder (sgi2All as (sgi, _), env) =
adamc@31 1154 let
adamc@31 1155 fun seek p =
adamc@31 1156 let
adamc@31 1157 fun seek env ls =
adamc@31 1158 case ls of
adamc@31 1159 [] => (sgnError env (UnmatchedSgi sgi2All);
adamc@31 1160 env)
adamc@31 1161 | h :: t =>
adamc@31 1162 case p h of
adamc@31 1163 NONE => seek (E.sgiBinds env h) t
adamc@31 1164 | SOME env => env
adamc@31 1165 in
adamc@31 1166 seek env sgis1
adamc@31 1167 end
adamc@31 1168 in
adamc@31 1169 case sgi of
adamc@31 1170 L'.SgiConAbs (x, n2, k2) =>
adamc@31 1171 seek (fn sgi1All as (sgi1, _) =>
adamc@31 1172 let
adamc@41 1173 fun found (x', n1, k1, co1) =
adamc@41 1174 if x = x' then
adamc@41 1175 let
adamc@41 1176 val () = unifyKinds k1 k2
adamc@41 1177 handle KUnify (k1, k2, err) =>
adamc@41 1178 sgnError env (SgiWrongKind (sgi1All, k1, sgi2All, k2, err))
adamc@41 1179 val env = E.pushCNamedAs env x n1 k1 co1
adamc@41 1180 in
adamc@41 1181 SOME (if n1 = n2 then
adamc@41 1182 env
adamc@41 1183 else
adamc@41 1184 E.pushCNamedAs env x n2 k2 (SOME (L'.CNamed n1, loc2)))
adamc@41 1185 end
adamc@41 1186 else
adamc@41 1187 NONE
adamc@31 1188 in
adamc@31 1189 case sgi1 of
adamc@41 1190 L'.SgiConAbs (x', n1, k1) => found (x', n1, k1, NONE)
adamc@41 1191 | L'.SgiCon (x', n1, k1, c1) => found (x', n1, k1, SOME c1)
adamc@31 1192 | _ => NONE
adamc@31 1193 end)
adamc@31 1194
adamc@31 1195 | L'.SgiCon (x, n2, k2, c2) =>
adamc@31 1196 seek (fn sgi1All as (sgi1, _) =>
adamc@31 1197 case sgi1 of
adamc@41 1198 L'.SgiCon (x', n1, k1, c1) =>
adamc@41 1199 if x = x' then
adamc@41 1200 let
adamc@41 1201 val () = unifyCons env c1 c2
adamc@41 1202 handle CUnify (c1, c2, err) =>
adamc@41 1203 sgnError env (SgiWrongCon (sgi1All, c1, sgi2All, c2, err))
adamc@41 1204 in
adamc@41 1205 SOME (E.pushCNamedAs env x n2 k2 (SOME c2))
adamc@41 1206 end
adamc@41 1207 else
adamc@41 1208 NONE
adamc@31 1209 | _ => NONE)
adamc@31 1210
adamc@32 1211 | L'.SgiVal (x, n2, c2) =>
adamc@32 1212 seek (fn sgi1All as (sgi1, _) =>
adamc@32 1213 case sgi1 of
adamc@41 1214 L'.SgiVal (x', n1, c1) =>
adamc@41 1215 if x = x' then
adamc@41 1216 let
adamc@41 1217 val () = unifyCons env c1 c2
adamc@41 1218 handle CUnify (c1, c2, err) =>
adamc@41 1219 sgnError env (SgiWrongCon (sgi1All, c1, sgi2All, c2, err))
adamc@41 1220 in
adamc@41 1221 SOME env
adamc@41 1222 end
adamc@41 1223 else
adamc@41 1224 NONE
adamc@32 1225 | _ => NONE)
adamc@32 1226
adamc@33 1227 | L'.SgiStr (x, n2, sgn2) =>
adamc@33 1228 seek (fn sgi1All as (sgi1, _) =>
adamc@33 1229 case sgi1 of
adamc@41 1230 L'.SgiStr (x', n1, sgn1) =>
adamc@41 1231 if x = x' then
adamc@41 1232 (subSgn env sgn1 sgn2;
adamc@41 1233 SOME env)
adamc@41 1234 else
adamc@41 1235 NONE
adamc@33 1236 | _ => NONE)
adamc@33 1237 (* Add type equations between structures here some day. *)
adamc@31 1238 end
adamc@31 1239 in
adamc@31 1240 ignore (foldl folder env sgis2)
adamc@31 1241 end
adamc@31 1242
adamc@41 1243 | (L'.SgnFun (m1, n1, dom1, ran1), L'.SgnFun (m2, n2, dom2, ran2)) =>
adamc@41 1244 (subSgn env dom2 dom1;
adamc@41 1245 subSgn env ran1 ran2)
adamc@41 1246
adamc@41 1247 | _ => sgnError env (SgnWrongForm (sgn1, sgn2))
adamc@41 1248
adamc@35 1249 fun selfify env {str, strs, sgn} =
adamc@35 1250 case #1 (hnormSgn env sgn) of
adamc@35 1251 L'.SgnError => sgn
adamc@35 1252 | L'.SgnVar _ => sgn
adamc@35 1253
adamc@35 1254 | L'.SgnConst sgis =>
adamc@35 1255 (L'.SgnConst (map (fn (L'.SgiConAbs (x, n, k), loc) =>
adamc@35 1256 (L'.SgiCon (x, n, k, (L'.CModProj (str, strs, x), loc)), loc)
adamc@35 1257 | (L'.SgiStr (x, n, sgn), loc) =>
adamc@35 1258 (L'.SgiStr (x, n, selfify env {str = str, strs = strs @ [x], sgn = sgn}), loc)
adamc@35 1259 | x => x) sgis), #2 sgn)
adamc@41 1260 | L'.SgnFun _ => sgn
adamc@42 1261 | L'.SgnWhere _ => sgn
adamc@35 1262
adamc@31 1263 fun elabDecl ((d, loc), env) =
adamc@30 1264 let
adamc@30 1265
adamc@30 1266 in
adamc@30 1267 resetKunif ();
adamc@30 1268 resetCunif ();
adamc@30 1269 case d of
adamc@30 1270 L.DCon (x, ko, c) =>
adamc@30 1271 let
adamc@30 1272 val k' = case ko of
adamc@30 1273 NONE => kunif ()
adamc@30 1274 | SOME k => elabKind k
adamc@3 1275
adamc@30 1276 val (c', ck) = elabCon env c
adamc@30 1277 val (env', n) = E.pushCNamed env x k' (SOME c')
adamc@30 1278 in
adamc@30 1279 checkKind env c' ck k';
adamc@6 1280
adamc@30 1281 if ErrorMsg.anyErrors () then
adamc@30 1282 ()
adamc@30 1283 else (
adamc@30 1284 if kunifsInKind k' then
adamc@30 1285 declError env (KunifsRemainKind (loc, k'))
adamc@30 1286 else
adamc@30 1287 ();
adamc@6 1288
adamc@30 1289 if kunifsInCon c' then
adamc@30 1290 declError env (KunifsRemainCon (loc, c'))
adamc@30 1291 else
adamc@30 1292 ()
adamc@30 1293 );
adamc@6 1294
adamc@31 1295 ((L'.DCon (x, n, k', c'), loc), env')
adamc@30 1296 end
adamc@30 1297 | L.DVal (x, co, e) =>
adamc@30 1298 let
adamc@30 1299 val (c', ck) = case co of
adamc@30 1300 NONE => (cunif ktype, ktype)
adamc@30 1301 | SOME c => elabCon env c
adamc@10 1302
adamc@30 1303 val (e', et) = elabExp env e
adamc@30 1304 val (env', n) = E.pushENamed env x c'
adamc@30 1305 in
adamc@30 1306 checkCon env e' et c';
adamc@10 1307
adamc@30 1308 if ErrorMsg.anyErrors () then
adamc@30 1309 ()
adamc@30 1310 else (
adamc@30 1311 if kunifsInCon c' then
adamc@30 1312 declError env (KunifsRemainCon (loc, c'))
adamc@30 1313 else
adamc@30 1314 ();
adamc@10 1315
adamc@30 1316 if cunifsInCon c' then
adamc@30 1317 declError env (CunifsRemainCon (loc, c'))
adamc@30 1318 else
adamc@30 1319 ();
adamc@10 1320
adamc@30 1321 if kunifsInExp e' then
adamc@30 1322 declError env (KunifsRemainExp (loc, e'))
adamc@30 1323 else
adamc@30 1324 ();
adamc@10 1325
adamc@30 1326 if cunifsInExp e' then
adamc@30 1327 declError env (CunifsRemainExp (loc, e'))
adamc@30 1328 else
adamc@30 1329 ());
adamc@10 1330
adamc@31 1331 ((L'.DVal (x, n, c', e'), loc), env')
adamc@30 1332 end
adamc@30 1333
adamc@31 1334 | L.DSgn (x, sgn) =>
adamc@31 1335 let
adamc@31 1336 val sgn' = elabSgn env sgn
adamc@31 1337 val (env', n) = E.pushSgnNamed env x sgn'
adamc@31 1338 in
adamc@31 1339 ((L'.DSgn (x, n, sgn'), loc), env')
adamc@31 1340 end
adamc@31 1341
adamc@31 1342 | L.DStr (x, sgno, str) =>
adamc@31 1343 let
adamc@31 1344 val formal = Option.map (elabSgn env) sgno
adamc@31 1345 val (str', actual) = elabStr env str
adamc@31 1346
adamc@35 1347 fun self (str, _) =
adamc@35 1348 case str of
adamc@35 1349 L'.StrVar x => SOME (x, [])
adamc@35 1350 | L'.StrProj (str, x) =>
adamc@35 1351 (case self str of
adamc@35 1352 NONE => NONE
adamc@35 1353 | SOME (m, ms) => SOME (m, ms @ [x]))
adamc@35 1354 | _ => NONE
adamc@35 1355
adamc@31 1356 val sgn' = case formal of
adamc@35 1357 NONE =>
adamc@35 1358 (case self str' of
adamc@35 1359 NONE => actual
adamc@35 1360 | SOME (str, strs) => selfify env {sgn = actual, str = str, strs = strs})
adamc@31 1361 | SOME formal =>
adamc@31 1362 (subSgn env actual formal;
adamc@31 1363 formal)
adamc@31 1364
adamc@31 1365 val (env', n) = E.pushStrNamed env x sgn'
adamc@31 1366 in
adamc@31 1367 ((L'.DStr (x, n, sgn', str'), loc), env')
adamc@31 1368 end
adamc@30 1369 end
adamc@3 1370
adamc@31 1371 and elabStr env (str, loc) =
adamc@31 1372 case str of
adamc@31 1373 L.StrConst ds =>
adamc@31 1374 let
adamc@31 1375 val (ds', env') = ListUtil.foldlMap elabDecl env ds
adamc@31 1376 val sgis = List.mapPartial sgiOfDecl ds'
adamc@31 1377 in
adamc@31 1378 ((L'.StrConst ds', loc), (L'.SgnConst sgis, loc))
adamc@31 1379 end
adamc@31 1380 | L.StrVar x =>
adamc@31 1381 (case E.lookupStr env x of
adamc@31 1382 NONE =>
adamc@31 1383 (strError env (UnboundStr (loc, x));
adamc@31 1384 (strerror, sgnerror))
adamc@31 1385 | SOME (n, sgn) => ((L'.StrVar n, loc), sgn))
adamc@34 1386 | L.StrProj (str, x) =>
adamc@34 1387 let
adamc@34 1388 val (str', sgn) = elabStr env str
adamc@34 1389 in
adamc@34 1390 case E.projectStr env {str = str', sgn = sgn, field = x} of
adamc@34 1391 NONE => (strError env (UnboundStr (loc, x));
adamc@34 1392 (strerror, sgnerror))
adamc@34 1393 | SOME sgn => ((L'.StrProj (str', x), loc), sgn)
adamc@34 1394 end
adamc@41 1395 | L.StrFun (m, dom, ranO, str) =>
adamc@41 1396 let
adamc@41 1397 val dom' = elabSgn env dom
adamc@41 1398 val (env', n) = E.pushStrNamed env m dom'
adamc@41 1399 val (str', actual) = elabStr env' str
adamc@41 1400
adamc@41 1401 val formal =
adamc@41 1402 case ranO of
adamc@41 1403 NONE => actual
adamc@41 1404 | SOME ran =>
adamc@41 1405 let
adamc@42 1406 val ran' = elabSgn env' ran
adamc@41 1407 in
adamc@41 1408 subSgn env' actual ran';
adamc@41 1409 ran'
adamc@41 1410 end
adamc@41 1411 in
adamc@41 1412 ((L'.StrFun (m, n, dom', formal, str'), loc),
adamc@41 1413 (L'.SgnFun (m, n, dom', formal), loc))
adamc@41 1414 end
adamc@31 1415
adamc@31 1416 val elabFile = ListUtil.foldlMap elabDecl
adamc@2 1417
adamc@2 1418 end