bar(vars Open, vars High, vars Low, vars Close, vars Price, DATE Start, DATE Time): int 
User-supplied function for defining a bar; used to create special bar types such as Renko Bars or Range Bars, or to replace the mean price by a different algorithm. The function is called whenever a new price quote arrives or a price tick is read from a historical file. It can modify the candle and determine when the bar ends.

Parameters:
Open, High,
Low, Close, Price  Series with two elements of the corresponding price; f.i. Close[1] is the close price of the previous bar, and Close[0] is the most recent price. The prices of the current bar can be modified by the bar function. Price is the mean price and can be omitted when not used in the function. 
 
Start Optional start time of the bar in the OLE DATE format. Can be omitted when not used in the function.  
Time Optional time of the most recent tick resp. price quote. Can be omitted when not used in the function. 

Returns:
0 - close the bar at the normal end of the BarPeriod.
1 - close the bar now.
4 - keep the bar open until closed by returning 1, and call the bar function at every price tick. 
8 - call the bar function only once at the end of every bar. 

	// Haiken Ashi Bars
int bar(vars Open,vars High,vars Low,vars Close)
{
  Close[0] = (Open[0]+High[0]+Low[0]+Close[0])/4;
  Open[0] = (Open[1]+Close[1])/2;
  High[0] = max(High[0],max(Open[0],Close[0]));
  Low[0] = min(Low[0],min(Open[0],Close[0]));
  return 8;
}

function run() {
	vars Open = series(priceOpen());
	vars High = series(priceHigh());
	vars Low = series(priceLow());
	vars Close = series(priceClose());
	vars Price = series(price());
	ColorUp = BLUE;
	ColorDn = MAGENTA;
}

bool change;
if ((Close[0] > Close[1] and Close[1] < Close[2]) or (Close[0] < Close[1] and Close[1] > Close[2])) change = true;