Swift concatenate two Ranges
<p>I have two Ranges:</p>

<pre><code>let r1: Range&lt;Int&gt; = 1...3
let r2: Range&lt;Int&gt; = 10...12
</code></pre>

<p>Is there a Swift way to concat/join the two ranges such that I can iterate over both of them in one <code>for</code> loop?</p>

<pre><code>for i in joined_r1_and_r2 {
    print(i)
}
</code></pre>

<p>Where the results would be:</p>

<pre><code>1
2
3
10
11
12
</code></pre>