如何在WKNavigationAction中读取syntheticClickType值

Question

import WebKit
let action = WKNavigationAction()
print("\(action.syntheticClickType)")

最终会出现错误消息：

error: value of type 'WKNavigationAction' has no member 'syntheticClickType'
action.syntheticClickType

是否有可能以某种方式获取syntheticClickType的值？