a><code><span><span class="keyword">val</span> succs : <span><a href="#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><a href="#type-state">state</a> <span class="arrow">&#45;&gt;</span></span> <a href="States/index.html#type-t">States.t</a></span></code></div><div class="spec-doc"><p><code>succs s q</code> returns the set of immediate successors in <code>s</code>, <i>i.e.</i> the set of state <code>q'</code> such that there exists a transition <code>(q,l,q')</code> in <code>R</code>. Raise