[vim] To switch from vertical split to horizontal split fast in Vim

Inspired by Steve answer, I wrote simple function that toggles between vertical and horizontal splits for all windows in current tab. You can bind it to mapping like in the last line below.

function! ToggleWindowHorizontalVerticalSplit()
  if !exists('t:splitType')
    let t:splitType = 'vertical'
  endif

  if t:splitType == 'vertical' " is vertical switch to horizontal
    windo wincmd K
    let t:splitType = 'horizontal'

  else " is horizontal switch to vertical
    windo wincmd H
    let t:splitType = 'vertical'
  endif
endfunction

nnoremap <silent> <leader>wt :call ToggleWindowHorizontalVerticalSplit()<cr>