adamc@26: (* Copyright (c) 2008, Adam Chlipala
adamc@26:  * All rights reserved.
adamc@26:  *
adamc@26:  * Redistribution and use in source and binary forms, with or without
adamc@26:  * modification, are permitted provided that the following conditions are met:
adamc@26:  *
adamc@26:  * - Redistributions of source code must retain the above copyright notice,
adamc@26:  *   this list of conditions and the following disclaimer.
adamc@26:  * - Redistributions in binary form must reproduce the above copyright notice,
adamc@26:  *   this list of conditions and the following disclaimer in the documentation
adamc@26:  *   and/or other materials provided with the distribution.
adamc@26:  * - The names of contributors may not be used to endorse or promote products
adamc@26:  *   derived from this software without specific prior written permission.
adamc@26:  *
adamc@26:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@26:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@26:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@26:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@26:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
adamc@26:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@26:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@26:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@26:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@26:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@26:  * POSSIBILITY OF SUCH DAMAGE.
adamc@26:  *)
adamc@26: 
adamc@26: structure FlatEnv :> FLAT_ENV = struct
adamc@26: 
adamc@26: open Flat
adamc@26: 
adamc@26: structure IM = IntBinaryMap
adamc@26: 
adamc@26: 
adamc@26: exception UnboundRel of int
adamc@26: exception UnboundNamed of int
adamc@26: exception UnboundF of int
adamc@26: 
adamc@26: type env = {
adamc@26:      namedT : (string * typ option) IM.map,
adamc@26: 
adamc@26:      relE : (string * typ) list,
adamc@26:      namedE : (string * typ) IM.map,
adamc@26: 
adamc@26:      F : (string * typ * typ) IM.map
adamc@26: }
adamc@26: 
adamc@26: val empty = {
adamc@26:     namedT = IM.empty,
adamc@26: 
adamc@26:     relE = [],
adamc@26:     namedE = IM.empty,
adamc@26: 
adamc@26:     F = IM.empty
adamc@26: }
adamc@26: 
adamc@26: fun pushTNamed (env : env) x n co =
adamc@26:     {namedT = IM.insert (#namedT env, n, (x, co)),
adamc@26: 
adamc@26:      relE = #relE env,
adamc@26:      namedE = #namedE env,
adamc@26: 
adamc@26:      F = #F env}
adamc@26: 
adamc@26: fun lookupTNamed (env : env) n =
adamc@26:     case IM.find (#namedT env, n) of
adamc@26:         NONE => raise UnboundNamed n
adamc@26:       | SOME x => x
adamc@26: 
adamc@26: fun pushERel (env : env) x t =
adamc@26:     {namedT = #namedT env,
adamc@26: 
adamc@26:      relE = (x, t) :: #relE env,
adamc@26:      namedE = #namedE env,
adamc@26: 
adamc@26:      F = #F env}
adamc@26: 
adamc@26: fun lookupERel (env : env) n =
adamc@26:     (List.nth (#relE env, n))
adamc@26:     handle Subscript => raise UnboundRel n
adamc@26: 
adamc@26: fun listERels (env : env) = #relE env
adamc@26: 
adamc@26: fun pushENamed (env : env) x n t =
adamc@26:     {namedT = #namedT env,
adamc@26: 
adamc@26:      relE = #relE env,
adamc@26:      namedE = IM.insert (#namedE env, n, (x, t)),
adamc@26: 
adamc@26:      F = #F env}
adamc@26: 
adamc@26: fun lookupENamed (env : env) n =
adamc@26:     case IM.find (#namedE env, n) of
adamc@26:         NONE => raise UnboundNamed n
adamc@26:       | SOME x => x
adamc@26: 
adamc@26: fun pushF (env : env) n x dom ran =
adamc@26:     {namedT = #namedT env,
adamc@26: 
adamc@26:      relE = #relE env,
adamc@26:      namedE = #namedE env,
adamc@26: 
adamc@26:      F = IM.insert (#F env, n, (x, dom, ran))}
adamc@26: 
adamc@26: fun lookupF (env : env) n =
adamc@26:     case IM.find (#F env, n) of
adamc@26:         NONE => raise UnboundF n
adamc@26:       | SOME x => x
adamc@26: 
adamc@26: fun declBinds env (d, _) =
adamc@26:     case d of
adamc@26:         DVal (x, n, t, _) => pushENamed env x n t
adamc@26:       | DFun (n, x, dom, ran, _) => pushF env n x dom ran
adamc@26: 
adamc@26: end