/**
  * Copyright (c): Uwe Schmidt, FH Wedel
  *
  * You may study, modify and distribute this source code
  * FOR NON-COMMERCIAL PURPOSES ONLY.
  * This copyright message has to remain unchanged.
  *
  * Note that this document is provided 'as is',
  * WITHOUT WARRANTY of any kind either expressed or implied.
  */

/**
 * eine Klasse Symbol fuer Namen als Atome
 *
 * ein Name wird durch einen Java String
 * repraesentiert
 */

//--------------------

class Symbol extends Atom {

  protected final
  String name;

  //--------------------

  public
  Symbol(String name) {
    this.name = name;
  }

  //--------------------

  // isEqual muss redefiniert werden

  public
  SExpr isEqual(SExpr e2) {

    if ( this == e2 )
      return
	t;

    if ( ! ( e2 instanceof Symbol ) )
      return
	nil;

    if ( name.equals( ((Symbol)e2).name ) )
      return
	t;

    return
      nil;
  }

  //--------------------

  public
  String toString() {
    return
      name;
  }
}