--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/flat_util.sig	Tue Jun 10 15:56:33 2008 -0400
@@ -0,0 +1,122 @@
+(* 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.
+ *)
+
+signature FLAT_UTIL = sig
+
+structure Typ : sig
+    val mapfold : (Flat.typ', 'state, 'abort) Search.mapfolder
+                  -> (Flat.typ, 'state, 'abort) Search.mapfolder
+
+    val map : (Flat.typ' -> Flat.typ')
+              -> Flat.typ -> Flat.typ
+
+    val fold : (Flat.typ' * 'state -> 'state)
+              -> 'state -> Flat.typ -> 'state
+
+    val exists : (Flat.typ' -> bool) -> Flat.typ -> bool
+end
+
+structure Exp : sig
+    datatype binder =
+             NamedT of string * int * Flat.typ option
+           | RelE of string * Flat.typ
+           | NamedE of string * int * Flat.typ * Flat.exp option
+
+    val mapfoldB : {typ : (Flat.typ', 'state, 'abort) Search.mapfolder,
+                    exp : ('typtext, Flat.exp', 'state, 'abort) Search.mapfolderB,
+                    bind : 'typtext * binder -> 'typtext}
+                   -> ('typtext, Flat.exp, 'state, 'abort) Search.mapfolderB
+    val mapfold : {typ : (Flat.typ', 'state, 'abort) Search.mapfolder,
+                   exp : (Flat.exp', 'state, 'abort) Search.mapfolder}
+                  -> (Flat.exp, 'state, 'abort) Search.mapfolder
+
+    val map : {typ : Flat.typ' -> Flat.typ',
+               exp : Flat.exp' -> Flat.exp'}
+              -> Flat.exp -> Flat.exp
+    val mapB : {typ : Flat.typ' -> Flat.typ',
+                exp : 'typtext -> Flat.exp' -> Flat.exp',
+                bind : 'typtext * binder -> 'typtext}
+               -> 'typtext -> (Flat.exp -> Flat.exp)
+
+    val fold : {typ : Flat.typ' * 'state -> 'state,
+                exp : Flat.exp' * 'state -> 'state}
+               -> 'state -> Flat.exp -> 'state
+                                        
+    val exists : {typ : Flat.typ' -> bool,
+                  exp : Flat.exp' -> bool} -> Flat.exp -> bool
+end
+
+structure Decl : sig
+    datatype binder = datatype Exp.binder
+
+    val mapfoldB : {typ : (Flat.typ', 'state, 'abort) Search.mapfolder,
+                    exp : ('typtext, Flat.exp', 'state, 'abort) Search.mapfolderB,
+                    decl : ('typtext, Flat.decl', 'state, 'abort) Search.mapfolderB,
+                    bind : 'typtext * binder -> 'typtext}
+                   -> ('typtext, Flat.decl, 'state, 'abort) Search.mapfolderB
+    val mapfold : {typ : (Flat.typ', 'state, 'abort) Search.mapfolder,
+                   exp : (Flat.exp', 'state, 'abort) Search.mapfolder,
+                   decl : (Flat.decl', 'state, 'abort) Search.mapfolder}
+                  -> (Flat.decl, 'state, 'abort) Search.mapfolder
+
+    val fold : {typ : Flat.typ' * 'state -> 'state,
+                exp : Flat.exp' * 'state -> 'state,
+                decl : Flat.decl' * 'state -> 'state}
+               -> 'state -> Flat.decl -> 'state
+end
+
+structure File : sig
+    datatype binder =
+             NamedT of string * int * Flat.typ option
+           | RelE of string * Flat.typ
+           | NamedE of string * int * Flat.typ * Flat.exp option
+           | F of int * string * Flat.typ * Flat.typ * Flat.exp
+
+    val mapfoldB : {typ : (Flat.typ', 'state, 'abort) Search.mapfolder,
+                    exp : ('typtext, Flat.exp', 'state, 'abort) Search.mapfolderB,
+                    decl : ('typtext, Flat.decl', 'state, 'abort) Search.mapfolderB,
+                    bind : 'typtext * binder -> 'typtext}
+                   -> ('typtext, Flat.file, 'state, 'abort) Search.mapfolderB
+
+    val mapfold : {typ : (Flat.typ', 'state, 'abort) Search.mapfolder,
+                   exp : (Flat.exp', 'state, 'abort) Search.mapfolder,
+                   decl : (Flat.decl', 'state, 'abort) Search.mapfolder}
+                  -> (Flat.file, 'state, 'abort) Search.mapfolder
+
+    val mapB : {typ : Flat.typ' -> Flat.typ',
+                exp : 'typtext -> Flat.exp' -> Flat.exp',
+                decl : 'typtext -> Flat.decl' -> Flat.decl',
+                bind : 'typtext * binder -> 'typtext}
+               -> 'typtext -> Flat.file -> Flat.file
+
+    val fold : {typ : Flat.typ' * 'state -> 'state,
+                exp : Flat.exp' * 'state -> 'state,
+                decl : Flat.decl' * 'state -> 'state}
+               -> 'state -> Flat.file -> 'state
+end
+
+end