Task

Create a directory and any missing parents.

This task is named after the posix mkdir -p command, and several libraries which implement the same behavior.

Please implement a function of a single path string (for example ./path/to/dir) which has the above side-effect.
If the directory already exists, return successfully.
Ideally implementations will work equally well cross-platform (on windows, linux, and OS X).

It's likely that your language implements such a function as part of its standard library. If so, please also show how such a function would be implemented.




require("lfs")
 
function mkdir (path)
  local sep, pStr = package.config:sub(1, 1), ""
  for dir in path:gmatch("[^" .. sep .. "]+") do
    pStr = pStr .. dir .. sep
    lfs.mkdir(pStr)
  end
end
 
mkdir("C:\\path\\to\\dir") -- Quoting backslashes requires escape sequence