Clojure CLI command line tool

[practicalli-johnny]

A basic template for creating a Clojure CLI command tool.

   (ns practicalli.tool-name
    (:gen-class)
    (:require [clojure.tools.cli :as cli]))

  (def VERSION "0.0.1")

  (def cli-opts
    [["-v" "--verbose" "Increase verbosity" :default 0 :update-fn inc]
     [nil  "--version" "Print version and exit"]
     ["-h" "--help" "Print this help information"]])

  (defn exec-tool [args {:keys [] :as opts}]
    ;; main functionality goes here, you get a seq of positional arguments, and a
    ;; map of options.
    )

  (defn -main [& args]
    (let [{:keys [errors options arguments summary]} (cli/parse-opts args cli-opts)]
      (cond
        (seq errors)
        (do
          (run! println errors)
          (println summary)
          (System/exit -1)) ;; non-zero exit code if something goes wrong

        (:help options)
        (do
          (println summary)
          (System/exit 0))

        (:version options)
        (do
          (println VERSION)
          (System/exit 0))

        :else
        (main arguments options))))