annotate src/elaborate.sml @ 2:64f09f7822c3

Start of elaboration
author Adam Chlipala <adamc@hcoop.net>
date Sat, 26 Jan 2008 14:27:33 -0500
parents
children daa4f1d7a663
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@2 30 structure L = Laconic
adamc@2 31 structure L' = Elab
adamc@2 32 structure E = ElabEnv
adamc@2 33 structure U = ElabUtil
adamc@2 34
adamc@2 35 fun elabKind (k, loc) =
adamc@2 36 case k of
adamc@2 37 L.KType => (L'.KType, loc)
adamc@2 38 | L.KArrow (k1, k2) => (L'.KArrow (elabKind k1, elabKind k2), loc)
adamc@2 39 | L.KName => (L'.KName, loc)
adamc@2 40 | L.KRecord k => (L'.KRecord (elabKind k), loc)
adamc@2 41
adamc@2 42 fun elabExplicitness e =
adamc@2 43 case e of
adamc@2 44 L.Explicit => L'.Explicit
adamc@2 45 | L.Implicit => L'.Implicit
adamc@2 46
adamc@2 47 fun occursKind r =
adamc@2 48 U.Kind.exists (fn L'.KUnif (_, r') => r = r'
adamc@2 49 | _ => false)
adamc@2 50
adamc@2 51 datatype unify_error =
adamc@2 52 KOccursCheckFailed of L'.kind * L'.kind
adamc@2 53 | KIncompatible of L'.kind * L'.kind
adamc@2 54
adamc@2 55 fun unifyError err =
adamc@2 56 case err of
adamc@2 57 KOccursCheckFailed (k1, k2) =>
adamc@2 58 ErrorMsg.errorAt (#2 k1) "Kind occurs check failed"
adamc@2 59 | KIncompatible (k1, k2) =>
adamc@2 60 ErrorMsg.errorAt (#2 k1) "Incompatible kinds"
adamc@2 61
adamc@2 62 fun unifyKinds (k1All as (k1, pos)) (k2All as (k2, _)) =
adamc@2 63 let
adamc@2 64 fun err f = unifyError (f (k1All, k2All))
adamc@2 65 in
adamc@2 66 case (k1, k2) of
adamc@2 67 (L'.KType, L'.KType) => ()
adamc@2 68 | (L'.KArrow (d1, r1), L'.KArrow (d2, r2)) =>
adamc@2 69 (unifyKinds d1 d2;
adamc@2 70 unifyKinds r1 r2)
adamc@2 71 | (L'.KName, L'.KName) => ()
adamc@2 72 | (L'.KRecord k1, L'.KRecord k2) => unifyKinds k1 k2
adamc@2 73
adamc@2 74 | (L'.KError, _) => ()
adamc@2 75 | (_, L'.KError) => ()
adamc@2 76
adamc@2 77 | (L'.KUnif (_, ref (SOME k1All)), _) => unifyKinds k1All k2All
adamc@2 78 | (_, L'.KUnif (_, ref (SOME k2All))) => unifyKinds k1All k2All
adamc@2 79
adamc@2 80 | (L'.KUnif (_, r1), L'.KUnif (_, r2)) =>
adamc@2 81 if r1 = r2 then
adamc@2 82 ()
adamc@2 83 else
adamc@2 84 r1 := SOME k2All
adamc@2 85
adamc@2 86 | (L'.KUnif (_, r), _) =>
adamc@2 87 if occursKind r k2All then
adamc@2 88 err KOccursCheckFailed
adamc@2 89 else
adamc@2 90 r := SOME k2All
adamc@2 91 | (_, L'.KUnif (_, r)) =>
adamc@2 92 if occursKind r k1All then
adamc@2 93 err KOccursCheckFailed
adamc@2 94 else
adamc@2 95 r := SOME k1All
adamc@2 96
adamc@2 97 | _ => err KIncompatible
adamc@2 98 end
adamc@2 99
adamc@2 100 fun elabFile _ = raise Fail ""
adamc@2 101
adamc@2 102 end