"info">
A state. In our case, it is a list package we would like to see
    installed.<br>
</div>

<pre><span id="TYPEstate_space"><span class="keyword">type</span> <code class="type">'a</code> state_space</span> = <code class="type">'a array list</code> </pre>
<div class="info">
A state space. In our case, it is a collection of available
    packages: each cell contains all the versions available for one
    package, ordered by version.<br>
</div>

<br>
<h4 id="4_Integerspace">Integer space</h4><br>
<br>
T