File Paths in Clojure

In Clojure, we can use the clojure.java.io library to work with file paths. This library provides functions to handle file paths in a way that is portable across different operating systems.

(ns file-paths-example
  (:require [clojure.java.io :as io]
            [clojure.string :as str]))

(defn main []
  ;; `io/file` should be used to construct paths in a portable way.
  ;; It takes any number of arguments and constructs a hierarchical path from them.
  (let [p (str (io/file "dir1" "dir2" "filename"))]
    (println "p:" p)

  ;; You should always use `io/file` instead of concatenating slashes manually.
  ;; In addition to providing portability, `io/file` will also normalize paths.
    (println (str (io/file "dir1//" "filename")))
    (println (str (io/file "dir1/../dir1" "filename")))

  ;; `io/file` and various Java methods can be used to split a path.
    (println "Parent:" (.getParent (io/file p)))
    (println "Name:" (.getName (io/file p)))

  ;; We can check whether a path is absolute.
    (println (.isAbsolute (io/file "dir/file")))
    (println (.isAbsolute (io/file "/dir/file")))

    (let [filename "config.json"
          ;; Some file names have extensions following a dot.
          ;; We can split the extension out of such names.
          ext (second (str/split filename #"\."))]
      (println ext)
      ;; To find the file's name with the extension removed,
      ;; use `subs` and `str/index-of`.
      (println (subs filename 0 (str/index-of filename "."))))

  ;; `relativize` finds a relative path between a base and a target.
  ;; It returns the target if it cannot be made relative to base.
    (let [base (io/file "a/b")
          target1 (io/file "a/b/t/file")
          target2 (io/file "a/c/t/file")]
      (println (.toString (.relativize (.toPath base) (.toPath target1))))
      (println (.toString (.relativize (.toPath base) (.toPath target2))))))

(main)

To run this program, save it as file_paths_example.clj and use the Clojure command-line tool:

$ clj file_paths_example.clj
p: dir1/dir2/filename
dir1/filename
dir1/filename
Parent: dir1/dir2
Name: filename
false
true
json
config
t/file
../../c/t/file

This Clojure code demonstrates various file path operations similar to the original example. It uses the clojure.java.io library, which provides a cross-platform way to work with file paths. The io/file function is used to construct paths, similar to filepath.Join in Go.

Some differences to note:

Clojure doesn’t have a direct equivalent to Go’s filepath package. Instead, it leverages Java’s File class through the clojure.java.io library.
Path joining is done using io/file, which accepts multiple arguments.
For operations like getting the parent directory or file name, we use Java methods on the File object.
String manipulation functions from clojure.string are used for operations like splitting the file extension.
The relativize method from Java’s Path class is used to find relative paths.

These operations provide similar functionality to the Go example, allowing for portable file path manipulation in Clojure.

Line Filters in Clojure

Command Line Subcommands in Clojure

Learn X By Example

Title here

File Paths in Clojure