function! CmdLine(str)
  exe "menu Foo.Bar :" . a:str
  emenu Foo.Bar
  unmenu Foo
endfunction

function! VisualSelection(direction, extra_filter) range
  let l:saved_reg = @"
  execute "normal! vgvy"

  let l:pattern = escape(@", '\\/.*$^~[]')
  let l:pattern = substitute(l:pattern, "\n$", "", "")

  if a:direction == 'b'
    execute "normal ?" . l:pattern . "^M"
  elseif a:direction == 'gv'
    call CmdLine("vimgrep " . '/'. l:pattern . '/' . ' **/*.' . a:extra_filter)
  elseif a:direction == 'replace'
    call CmdLine("%s" . '/'. l:pattern . '/')
  elseif a:direction == 'f'
    execute "normal /" . l:pattern . "^M"
  endif

  let @/ = l:pattern
  let @" = l:saved_reg
endfunction