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<a name="Event-Designators"></a>
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<p>
Next: <a href="Word-Designators.html#Word-Designators" accesskey="n" rel="next">Word Designators</a>, Up: <a href="History-Interaction.html#History-Interaction" accesskey="u" rel="up">History Interaction</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Event-Designators-1"></a>
<h4 class="subsection">33.1.1 Event Designators</h4>
<a name="index-event-designators"></a>

<p>An event designator is a reference to a command line entry in the
history list.
Unless the reference is absolute, events are relative to the current
position in the history list.
<a name="index-history-events"></a>
</p>
<dl compact="compact">
<dt><code>!</code></dt>
<dd><p>Start a history substitution, except when followed by a space, tab,
the end of the line, or &lsquo;<samp>=</samp>&rsquo;.
</p>
</dd>
<dt><code>!<var>n</var></code></dt>
<dd><p>Refer to command line <var>n</var>.
</p>
</dd>
<dt><code>!-<var>n</var></code></dt>
<dd><p>Refer to the command <var>n</var> lines back.
</p>
</dd>
<dt><code>!!</code></dt>
<dd><p>Refer to the previous command.  This is a synonym for &lsquo;<samp>!-1</samp>&rsquo;.
</p>
</dd>
<dt><code>!<var>string</var></code></dt>
<dd><p>Refer to the most recent command
preceding the current position in the history list
starting with <var>string</var>.
</p>
</dd>
<dt><code>!?<var>string</var>[?]</code></dt>
<dd><p>Refer to the most recent command
preceding the current position in the history list
containing <var>string</var>.
The trailing
&lsquo;<samp>?</samp>&rsquo; may be omitted if the <var>string</var> is followed immediately by
a newline.
</p>
</dd>
<dt><code>^<var>string1</var>^<var>string2</var>^</code></dt>
<dd><p>Quick Substitution.  Repeat the last command, replacing <var>string1</var>
with <var>string2</var>.  Equivalent to
<code>!!:s/<var>string1</var>/<var>string2</var>/</code>.
</p>
</dd>
<dt><code>!#</code></dt>
<dd><p>The entire command line typed so far.
</p>
</dd>
</dl>


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