Match everything before first colon including colon and following spaces
<p>I'd like to match a string so that</p>

<pre><code>A: B: C
</code></pre>

<p>would return the match (note the space behind the colon)</p>

<pre><code>A: 
</code></pre>

<p>It matches everything until the first occurrence of a colon, but includes the colon and any spaces behind of it.</p>

<p>The pattern <code>^[^\:]+</code> would return <code>A</code> but not the colon and the spaces.</p>