public class PerlList extends Vector
{
   /*************************************************************
   * 
   *    constructors
   * 
   *************************************************************/
   public PerlList()
   {
      super();
   }
   
   public PerlList( int cap )
   {
      super( cap );
   }
   
   /*************************************************************
   * 
   *    push() and pop()
   * 
   *************************************************************/
   public void push( PerlList list )
   {
      Enumeration elems = list.elements();
      
      while( elems.hasMoreElements() )
         addElement( elems.nextElement() );
   }
   
   public void push( Object[] elems )
   {
      for( int i=0; i<elems.length; i++ )
         addElement( elems[i] );
   }

   public void push( Object scalar )
   {
      addElement( scalar );
   }
   
   public Object pop()
   {
      Object scalar = lastElement();
      removeElement( scalar );
      
      return scalar;
   }
   
   /*************************************************************
   * 
   *    shift() and unshift()
   * 
   *************************************************************/
   public Object shift()
   {
      Object scalar = firstElement();
      removeElement( scalar );
      
      return scalar;
   }
   
   public void unshift( Object scalar )
   {
      insertElementAt( scalar, 0 );
   }
     
   public void unshift( Object[] elems )
   {
      for( int i=0; i<elems.length; i++ )
         insertElementAt( elems[i], 0 );
   }
    
   public void unshift( PerlList list )
   {
      Enumeration elems = list.elements();
      
      while( elems.hasMoreElements() )
         insertElementAt( elems.nextElement(), 0 );
   }
   
   /*************************************************************
   * 
   *    split() and join()
   * 
   *************************************************************/
   
   public static PerlList split( String delims, String scalar )
   {
      PerlList l = new PerlList();
      
      StringTokenizer tok = new StringTokenizer( scalar, delims );
      
      while( tok.hasMoreTokens() )
      {
         l.push( tok.nextToken() );
      }
      
      return l;
   }
   
   public String join( String joiner )
   {
      StringBuffer buf   = new StringBuffer();
      Enumeration  elems = elements();
      
      if( elems.hasMoreElements() )
      {
         buf.append( (String) elems.nextElement() );
      }
      
      while( elems.hasMoreElements() )
      {
         buf.append( joiner );
         buf.append( (String) elems.nextElement() );
      }
      
      return buf.toString();      
   }
   
   
   public static String join( String joiner, PerlList[] list )
   {
      PerlList nu = new PerlList();
      
      for( int i=0; i<list.length; i++ )
         nu.push( list[i] );
         
      return nu.join( joiner );
   }
   
   
   /*************************************************************
   * 
   *    default access
   * 
   *************************************************************/
   public Object $( int index )
   {
      return (String) elementAt( index );
   }
   
   
   /*************************************************************
   * 
   *    test
   * 
   *************************************************************/
   public static void main( String args[] )
   {
      String a = "abcd 123-4 b  ag ag ag   x 567";
      
      PerlList pl = PerlList.split( " ", a );
      
      System.out.println( pl.join( "\n" ) );
      System.out.println( pl.$(0) );
   }

}