Unix/ls

Unix/ls
You are encouraged to solve this task according to the task description, using any language you may know.

Write a program that will list everything in the current folder, similar to the Unix utility “ls” [1] (or the Windows terminal command “DIR”). The output must be sorted, but printing extended details and producing multi-column output is not required.

Example output

For the list of paths:

/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b

When the program is executed in `/foo`, it should print:

bar

and when the program is executed in `/foo/bar`, it should print:

1
2
a
b

Clojure

<lang clojure>(def files (sort (filter #(= "." (.getParent %)) (file-seq (clojure.java.io/file ".")))))

(doseq [n files] (println (.getName n)))</lang>

D

<lang d>void main() {

   import std.stdio, std.file, std.path;

   foreach (const string path; dirEntries(getcwd, SpanMode.shallow))
       path.baseName.writeln;

}</lang>

Go

<lang Go>package main

import ( "fmt" "io/ioutil" "sort" )

func main() { info, err := ioutil.ReadDir(".") if err != nil { panic(err) }

files := []string{} for i := 0; i < len(info); i++ { files = append(files, info[i].Name()) } sort.Strings(files)

for i := 0; i < len(files); i++ { fmt.Printf("%s\n", files[i]) } }</lang>

J

<lang J> >{."#.1!:0'*'</lang>

Almost half of that is removing extra detail not relevant to this task.

OCaml

<lang ocaml>let () =

 Array.iter print_endline (
   Sys.readdir Sys.argv.(1) )</lang>

Output:

$ cd /foo/bar
$ ocaml ls.ml
1
2
a
b

PARI/GP

GP doesn't have this capability so we can either use the shell or PARI. For the latter see C; for the former: <lang parigp>system("dir/b/on")</lang> in DOS/Windows or <lang parigp>system("ls")</lang> in *nix.

Perl 6

There is a dir builtin command which returns a list of IO::Path objects. We stringify them all with a hyperoperator before sorting the strings.

<lang perl6>.say for sort ~«dir</lang>

Python

<lang python>>>> import os >>> print('\n'.join(sorted(os.listdir('.')))) DLLs Doc LICENSE.txt Lib NEWS.txt README.txt Scripts Tools include libs python.exe pythonw.exe tcl >>> </lang>

REXX

The following program works under Windows and used the Windows DIR command to list a bare-bones sorted list. <lang rexx>/*REXX program lists contents of current folder (ala mode UNIX's LS). */ 'DIR /b /oN' /*use Windows DIR: sorts & lists.*/

                                      /*stick a fork in it, we're done.*/</lang>

Ruby

<lang ruby> Dir.foreach("./"){|n| puts n} </lang> This will output all files including hidden ones e.g. '.' and '..'.

Rust

<lang rust>use std::os; use std::io::fs;

fn main() { let cwd = os::getcwd(); let info = fs::readdir(&cwd).unwrap();

let mut filenames = Vec::new(); for entry in info.iter() { filenames.push(entry.filename_str().unwrap()); }

filenames.sort(); for filename in filenames.iter() { println!("{}", filename); } }</lang>

Tcl

<lang tcl>puts [join [lsort [glob -nocomplain *]] "\n"]</lang>

zkl

<lang zkl>File.glob("*").println()</lang> Lists all files and directories in the current directory. If you only want a list of files: <lang zkl> File.glob("*",0x8)</lang> The glob method uses Unix shell wild cards.

The globular method recurses down through the directories.