(*****************************************************************************
 * su4sml --- an SML repository for managing (Secure)UML/OCL models
 *             http://projects.brucker.ch/su4sml/
 *                                                                            
 * HashTable.sml --- 
 * This file is part of su4sml.
 *
 * Copyright (c) 2005-2007, ETH Zurich, Switzerland
 *
 * 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.
 *
 *     * Neither the name of the copyright holders nor the names of its
 *       contributors may 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.
 ******************************************************************************)
(* $Id$ *)

structure HashString = 
struct 
fun hashString _ = ()
end

structure HashTable = 
struct 

		  
datatype ('a, 'b) hash_table = HT of {
	 eq_pred : ('a * 'a) -> bool,
	 not_found : exn,
	 table: (('a*'b) list) ref
}




fun mkTable (_, eq) (_, notFound) = HT{
	    eq_pred = eq,
	    not_found = notFound,
	    table = ref ([])
	  }


fun find    (HT{table,...}) key =
                           Option.map (fn (a,b) => b) ((List.find (fn (x,y) => x =key) (!table))) 
fun insert  (HT{table,...}) (k,v) =  (table:=([(k,v)]@ (!(table))))

end