Ruby, Shortest way to create Key, value pair out of hash?
<p>I have hash like this:</p>

<pre><code>h = {
   type1: [1,2,3,4],
   type2: [1,2,3,4],
   type3: [1,2,3,4]
}
</code></pre>

<p>I want output like this:</p>

<pre><code>[[:type1,1],[:type1,2],[:type1,3],[:type1,4],[:type2,1],[:type2,2] ... ]
</code></pre>

<p>I will not be using it in actual code as it's much more easier to write, understand and read simple block statement, but for curiosity sake. What is the very rubyist way to do it, disregarding any performance concerns if need be.</p>