Pine-script绘制无垂直连接线的阶梯线

//@version=4
study("Staircase Line", overlay=true)

var float prevClose = na
var line lineSegment = na

if not na(close)
    if na(prevClose)
        prevClose := close
    else if close > prevClose
        lineSegment := line.new(bar_index - 1, prevClose, bar_index, close, color=color.green)
    else if close < prevClose
        lineSegment := line.new(bar_index - 1, prevClose, bar_index, close, color=color.red)
    else
        lineSegment := line.new(bar_index - 1, prevClose, bar_index, close, color=color.blue)

    prevClose := close

line.delete(lineSegment[1])