Task

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



iex(1)> ls = fn dir -> File.ls!(dir) |> Enum.each(&IO.puts &1) end
#Function<6.54118792/1 in :erl_eval.expr/5>
iex(2)> ls.("foo")
bar
:ok
iex(3)> ls.("foo/bar")
1
2
a
b
:ok