What's the easiest way to parse numbers in clojure?

Question

I\'ve been using java to parse numbers, e.g.

(. Integer parseInt  numberString)

Is there a more clojuriffic way that would handle both int

Answer 1

I find solussd's answer work great for my code. Based on it, here's an enhancement with support for Scientific notation. Besides, (.trim s) is added so that extra space can be tolerated.

(defn parse-number
  "Reads a number from a string. Returns nil if not a number."
  [s]
  (if (re-find #"^-?\d+\.?\d*([Ee]\+\d+|[Ee]-\d+|[Ee]\d+)?$" (.trim s))
    (read-string s)))

e.g.

(parse-number "  4.841192E-002  ")    ;=> 0.04841192
(parse-number "  4.841192e2 ")    ;=> 484.1192
(parse-number "  4.841192E+003 ")    ;=> 4841.192
(parse-number "  4.841192e.2 ")  ;=> nil
(parse-number "  4.841192E ")  ;=> nil