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/*
 * Distributed as part of mchange-commons-scala v0.4.0
 *
 * Copyright (C) 2015 Machinery For Change, Inc.
 *
 * Author: Steve Waldman 
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of EITHER:
 *
 *     1) The GNU Lesser General Public License (LGPL), version 2.1, as 
 *        published by the Free Software Foundation
 *
 * OR
 *
 *     2) The Eclipse Public License (EPL), version 1.0
 *
 * You may choose which license to accept if you wish to redistribute
 * or modify this work. You may offer derivatives of this work
 * under the license you have chosen, or you may provide the same
 * choice of license which you have been offered here.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * You should have received copies of both LGPL v2.1 and EPL v1.0
 * along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
 * If not, the text of these licenses are currently available at
 *
 * LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 *  EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php 
 * 
 */

package com.mchange.sc.v1.lang;

object Union {
  // i think that, as a practical matter, this is probably not so useful

  // Miles Sabin's uboxed union type hack... see http://www.chuusai.com/2011/06/09/scala-union-types-curry-howard/
  type ¬[A] = A => Nothing;
  type ¬¬[A] = ¬[¬[A]];
  type v[T, U] = ¬[¬[T] with ¬[U]];
  type ~[T, U] = { type union[X] = ¬¬[X] <:< (T v U) };

  // def check[T : (String~Int)#union ]( arg : T ) = arg
}