Clojure range with a specific start and infinite end

Question

According to the docs the range function has four forms:

• (range) 0 - Infinity
• (range end) 0 - end
• (range start end) start - end
• (range start end step) start - end skipping by step

So how would I declare a range representing x to Infinity?

I may also be asking how do reference infinity, as something like (range x infinity) might work?

Answer 1

(iterate inc x) will give you a lazy, infinite sequence of numbers starting with x.

Answer 2

How about something like this:

(defn my-range
  ([start] (iterate inc' start))
  ([start step] (iterate #(+' % step) start)))

Please note inc' and +' to support arbitrary precision.