protected static Ptg calcAnd( Ptg[] operands )
	{
		boolean b = true;
		Ptg[] alloperands = PtgCalculator.getAllComponents( operands );
		for( Ptg alloperand : alloperands )
		{
			if( alloperand instanceof PtgBool )
			{
				PtgBool bo = (PtgBool) alloperand;
				Boolean bool = (Boolean) bo.getValue();
				if( bool == false )
				{
					return new PtgBool( false );
				}
			}
			else
			{
				// probably a ref, hopefully to a bool
				String s = String.valueOf( alloperand.getValue() );
				if( s.equalsIgnoreCase( "false" ) )
				{
					return new PtgBool( false );
				}
			}
		}
		return new PtgBool( true );
	}