code: /**
   *   Copyright (c) Rich Hickey. All rights reserved.
   *   The use and distribution terms for this software are covered by the
   *   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
   *   which can be found in the file epl-v10.html at the root of this distribution.
   *   By using this software in any fashion, you are agreeing to be bound by
   * 	 the terms of this license.
   *   You must not remove this notice, or any other, from this software.
   **/
  
  /* rich Mar 3, 2008 */
  
  package clojure.lang;
  
  public abstract class ATransientSet extends AFn implements ITransientSet{
  	volatile ITransientMap impl;
  
  	ATransientSet(ITransientMap impl) {
  		this.impl = impl;
  	}
  	
  	public int count() {
  		return impl.count();
  	}
  
  	public ITransientSet conj(Object val) {
  		ITransientMap m = impl.assoc(val, val);
  		if (m != impl) this.impl = m;
  		return this;
  	}
  
  	public boolean contains(Object key) {
  		return this != impl.valAt(key, this);
  	}
  
  	public ITransientSet disjoin(Object key)  {
  		ITransientMap m = impl.without(key);
  		if (m != impl) this.impl = m;
  		return this;
  	}
  
  	public Object get(Object key) {
  		return impl.valAt(key);
  	}
  
  	public Object invoke(Object key, Object notFound)  {
  		return impl.valAt(key, notFound);
  	}
  
  	public Object invoke(Object key)  {
  		return impl.valAt(key);	
  	}
  	
  }
  