问题
My case, I'm performing ngFor over ES6 collections that get filtered through pipe and converted into array, but when collection contains over 5000 elements ui starts acting sluggy, trivial performance profiling shown that creating large array per every dirty check is overkill, while iteration itself is fast.
So I would like to implement my own ngFor directive that would be capable of iterating through ES6 iterables.
It was simple in Angular 1, but it doesn't seem as easy in Angular 2, where should I start looking to accomplish that?
来源：https://stackoverflow.com/questions/39196756/creating-custom-ngfor-directive