Why Not a Function #20: add-leading-zeros
(defn add-leading-zeros
[n s]
(str/replace s #"\d+"
#(str/join (concat (repeat (- n (count %)) "0") [%]))))
add-leading-zeros
prepends numbers in the string with the 0 characters until each of the numbers reaches the desired length. It can be used, for example, for intelligent sorting.
(add-leading-zeros 3 "line 1: it's #wnaf #20! ")
=> "line 001: it's #wnaf #020! "
Written on April 7, 2020