How to iterate form array(array in array in array) in angular2 reactive forms?

Question

I tried to Iterate formArray several times,

This is plunker link for this case https://plnkr.co/edit/4kiJF7cL5VKwn3KnvjvK?p=preview

i want out put like this

Answer 1

I solved my problem

using <FormArray>this.roleForm.controls['permissionModules']).at(k).get('group') as FormArray

synatax I am able iterate nested arrays,

This is plunk link where you can see my approach http://plnkr.co/edit/AVqWKkUCNc1HjosOpUWf?p=preview