" Initialize directories {{{
function! InitializeDirectories()
  let parent = $HOME
  let prefix = 'vim'
  let dir_list = {
        \ 'backup': 'backupdir',
        \ 'swap': 'directory' }

  if has('persistent_undo')
    let dir_list['undo'] = 'undodir'
  endif

  let common_dir = parent . '/.' . prefix

  for [dirname, settingname] in items(dir_list)
    let directory = common_dir . dirname . '/'
    if exists("*mkdir")
      if !isdirectory(directory)
        call mkdir(directory)
      endif
    endif
    if !isdirectory(directory)
      echo "Warning: Unable to create backup directory: " . directory
      echo "Try: mkdir -p " . directory
    else
      let directory = substitute(directory, " ", "\\\\ ", "g")
      exec "set " . settingname . "=" . directory
    endif
  endfor
endfunction
call InitializeDirectories()
" }}}