How does one establish a processing loop in NIFI (the equivalent of a for loop, or a while loop)?

[#1]

There are many times when a data flow must include some kind of conditional looping.

How does one establish a processing loop in NIFI (the equivalent of a for loop, or a while loop)?

[#2]

One example I've found is this:

https://gist.github.com/ijokarumawak/01c4fd2d9291d3e74ec424a581659ca8

This looks relatively clean. Is this the best option?

[#3]

How can we pass dynamic attribute value in a loop condition.

Something like ${i:lt({$.count})},as i am getting error while putting up this condition in RouteToAttribute processor.

How can we achive this.Please help here.

,

How can we pass dynamic variable in a loop,for an instance i want to create a condition in RouteToAttribute like ${i:lt({$.count})}.

But as from the Nifi expression language doc we can only pass static value as a paremeter in lt().

How can it be achieved.Please help here.