--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/flat_env.sml	Tue Jun 10 15:56:33 2008 -0400
@@ -0,0 +1,126 @@
+(* 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 FlatEnv :> FLAT_ENV = struct
+
+open Flat
+
+structure IM = IntBinaryMap
+
+
+exception UnboundRel of int
+exception UnboundNamed of int
+exception UnboundF of int
+
+type env = {
+     namedT : (string * typ option) IM.map,
+
+     relE : (string * typ) list,
+     namedE : (string * typ) IM.map,
+
+     F : (string * typ * typ) IM.map
+}
+
+val empty = {
+    namedT = IM.empty,
+
+    relE = [],
+    namedE = IM.empty,
+
+    F = IM.empty
+}
+
+fun pushTNamed (env : env) x n co =
+    {namedT = IM.insert (#namedT env, n, (x, co)),
+
+     relE = #relE env,
+     namedE = #namedE env,
+
+     F = #F env}
+
+fun lookupTNamed (env : env) n =
+    case IM.find (#namedT env, n) of
+        NONE => raise UnboundNamed n
+      | SOME x => x
+
+fun pushERel (env : env) x t =
+    {namedT = #namedT env,
+
+     relE = (x, t) :: #relE env,
+     namedE = #namedE env,
+
+     F = #F env}
+
+fun lookupERel (env : env) n =
+    (List.nth (#relE env, n))
+    handle Subscript => raise UnboundRel n
+
+fun listERels (env : env) = #relE env
+
+fun pushENamed (env : env) x n t =
+    {namedT = #namedT env,
+
+     relE = #relE env,
+     namedE = IM.insert (#namedE env, n, (x, t)),
+
+     F = #F env}
+
+fun lookupENamed (env : env) n =
+    case IM.find (#namedE env, n) of
+        NONE => raise UnboundNamed n
+      | SOME x => x
+
+fun pushF (env : env) n x dom ran =
+    {namedT = #namedT env,
+
+     relE = #relE env,
+     namedE = #namedE env,
+
+     F = IM.insert (#F env, n, (x, dom, ran))}
+
+fun lookupF (env : env) n =
+    case IM.find (#F env, n) of
+        NONE => raise UnboundF n
+      | SOME x => x
+
+fun declBinds env (d, _) =
+    case d of
+        DVal (x, n, t, _) => pushENamed env x n t
+      | DFun (n, x, dom, ran, _) => pushF env n x dom ran
+
+fun bbind env x =
+    case ElabEnv.lookupC ElabEnv.basis x of
+        ElabEnv.NotBound => raise Fail "FlatEnv.bbind: Not bound"
+      | ElabEnv.Rel _ => raise Fail "FlatEnv.bbind: Rel"
+      | ElabEnv.Named (n, _) => pushTNamed env x n NONE
+
+val basis = empty
+val basis = bbind basis "int"
+val basis = bbind basis "float"
+val basis = bbind basis "string"
+
+end