HJKL repetition trap for Vim

gistfile1.vim

" HJKL repetition trap
" Barry Arthur, 2013-03-14
" depends on your   :help 'updatetime   setting

let g:cursor_moving = 0

function! TrapMovementKeys(key)
  augroup CursorMoving
    au!
    autocmd CursorMoved * let g:cursor_moving = 1
  augroup END
  if ! g:cursor_moving
    return a:key
  else
    return ''
  endif
endfunction

nnoremap <expr> h TrapMovementKeys('h')
nnoremap <expr> j TrapMovementKeys('j')
nnoremap <expr> k TrapMovementKeys('k')
nnoremap <expr> l TrapMovementKeys('l')

augroup CursorMovingOff
  au!
  autocmd CursorHold * let g:cursor_moving = 0
augroup END