.vimrc function to run script in VIM and display output in split window

shellworkflow.vim

function! s:ExecuteInShell(command)
  let command = join(map(split(a:command), 'expand(v:val)'))
  let winnr = bufwinnr('^' . command . '$')
  silent! execute ':w'
  silent! execute  winnr < 0 ? 'vnew ' . fnameescape(command) : winnr . 'wincmd w'
  setlocal buftype=nowrite bufhidden=wipe nobuflisted noswapfile nowrap number
  silent! execute 'silent %!'. command
  silent! redraw
  silent! execute 'au BufUnload <buffer> execute bufwinnr(' . bufnr('#') . ') . ''wincmd w'''
  silent! execute 'nnoremap <silent> <buffer> <LocalLeader>r :call <SID>ExecuteInShell(''' . command . ''')<CR>'
  silent! execute 'wincmd w'
  " echo 'Shell command ' . command . ' executed.'
endfunction
command! -complete=shellcmd -nargs=+ Shell call s:ExecuteInShell(<q-args>)
cabbrev shell Shell