bump.clj

bump.clj

#!/usr/bin/env bb
;; -*- mode: clojure -*-

(defn first-rest [col]
  [(first col) (rest col)])

(defn split-path [file]
  (let [file (io/file file)]
    [(.getParent file) (.getName file)]))

(defn numeric? [s]
  (let [s (drop-while #(Character/isDigit %) s)]
    (empty? s)))

(defn bad-filename [file]
  (binding [*out* *err*]
    (println (format "Bad filename: %s" file))
    (System/exit 2)))

(defn bump [file]
  (let [[parent basename] (split-path file)
        segments (str/split basename #"-")
        [old-number tail] (first-rest segments)]

    (when (or (empty? tail) (not (numeric? old-number)))
      (bad-filename file))

    (let [new-number (+ 1 (Integer/parseInt old-number))
          new-name (str/join "-" (cons new-number tail))]
      (io/file parent new-name))))

(let [[file] *command-line-args*]
  (when (empty? file)
    (println "Usage: <file>")
    (System/exit 1))
  (println (format "%s" (bump file))))