.vimrc

" <Space><C-n>, <Space><C-p>: Move window position {{{
nnoremap <silent> <Space><C-n> :<C-u> call <SID>swap_window(v:count1)<CR>
nnoremap <silent> <Space><C-p> :<C-u> call <SID>swap_window(-v:count1)<CR>

function! s:modulo(n, m) "{{{
  let d = a:n * a:m < 0 ? 1 : 0
  return a:n + (-(a:n + (0 < a:m ? d : -d)) / a:m + d) * a:m
endfunction "}}}

function! s:swap_window(n) "{{{
  let curbuf = bufnr('%')
  let target = s:modulo(winnr() + a:n - 1, winnr('$')) + 1

  execute 'hide' winbufnr(target) . 'buffer'
  execute target . 'wincmd w'
  execute curbuf . 'buffer'
endfunction "}}}
" }}}