function! RubyEndToken ()
  let current_line = getline( '.' )
  let braces_at_end = '{\s*\(|\(,\|\s\|\w\)*|\s*\)\?$'
  let brackets_at_end = '[\s*\(|\(,\|\s\|\w\)*|\s*\)\?$'
  let stuff_without_do = '^\s*\(class\|if\|unless\|begin\|case\|for\|module\|while\|until\|def\)'
  let with_do = 'do\s*\(|\(,\|\s\|\w\)*|\s*\)\?$'

  if match(current_line, braces_at_end) >= 0
    return "\<CR>}\<C-O>O"
  elseif match(current_line, brackets_at_end) >= 0
    return "\<CR>\1\<C-O>O"
  elseif match(current_line, stuff_without_do) >= 0
    return "\<CR>end\<C-O>O"
  elseif match(current_line, with_do) >= 0
    return "\<CR>end\<C-O>O"
  else
    return "\<CR>"
  endif
endfunction
autocmd FileType ruby,eruby inoremap <buffer> <CR> <C-R>=RubyEndToken()<CR>