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  <p>I’d recommend clicking the source link up there, as the diagram is interactive. You can click on the transitions and see how states change. That’s a big benefit of HSCs: not only are they formal and concise, they’re also kinetic. You can explore them.</p>

    </p>In exploring, I found a bug with my state machine: You can transition directly from Answers to Standards. We can fix that by making Answers a direct child of Login instead of a child of Reports:</p>

<iframe width="100%" height="400" frameborder="no" src=""></iframe>

<p>Ideally, we’d like to make these problems more obvious, which means using some form of automated verification.</p>




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