o the same number of tabs
and/or spaces as the previous line (or as the next line if the previous
line is the beginning of a paragraph).
</p>
</dd>
<dt><code>set backup</code></dt>
<dd><p>When saving a file, back up the previous version of it, using the current
filename suffixed with a tilde (<code>~</code>).
</p>
</dd>
<dt><code>set backupdir &quot;<var>directory</var>&quot;</code></dt>
<dd><p>Make and keep not just one backup file, but make and keep a uniquely
numbered one every time a file is saved &mdas