local function auto(event, opts)
  a.nvim_create_autocmd(event, opts)
end

a.nvim_create_augroup('bufcheck', { clear = true })

auto('TextYankPost', { -- highlight yanks
  group = 'bufcheck',
  pattern = '*',
  desc = 'Highlight on yank.',
  callback = function()
    vim.highlight.on_yank{ timeout = 250 }
  end
})

auto('BufRead', { -- return to last place
  pattern = '*',
  command = [[call setpos(".", getpos("'\""))]],
  desc = 'Return to the last place the buffer was closed in.',
})

auto('BufWritePre', { -- make dirs when they don't exist
  pattern = '*',
  group = vim.api.nvim_create_augroup('auto_create_dir', { clear = true }),
  desc = 'Basically mkdir -p.',
  callback = function(ctx)
    local dir = vim.fn.fnamemodify(ctx.file, ':p:h')
    vim.fn.mkdir(dir, 'p')
  end
})