Filter blank lines from implicit numbered registers

gistfile1.vim

" Barry Arthur, June 2015
" Don't store empty lines in implicit numbered registers.

let s:reg_9 = ''
function! FilterBlankReg1()
  let regs = map(range(9), "getreg(v:val+1)")
  if regs[0] == "\n"
    for reg in range(8)
      call setreg(reg+1, getreg(reg+2))
    endfor
    call setreg(9, s:reg_9)
  else
    let s:reg_9 = regs[8]
  endif
endfunction

augroup SkipBlankReg
  autocmd CursorMoved,CursorHold * call FilterBlankReg1()
augroup END