functional-programming - How to keep track of a list of nodes in the functional programming paradigm

Question

I just started to program in the functional paradigm and got stuck quite early on. I am trying to create a program that manages a peer to peer network. For this I have to keep track of a list of nodes in the network.

I have read a lot of articles about managing state in functional programming telling that state is managed though a tunnel of function calls. But this does not touch on the subject of the state when no functions are called, where is the state saved then?

I'd say that you use a database or something alike in this scenario but I was wondering if it was possible to do it runtime with functional programming.

标签： functional-programmingpersistence