&gt; and you don&#x27;t need any side-effects during its execution.<p>Have you seen any visualisations for pure functional programs? So they wouldn&#x27;t have any state&#x2F;side-effects but I can&#x27;t imagine how you&#x27;d visualise those usefully unless you only used small concrete example inputs and showed the function being evaluated. It is very interesting how some types of algorithms can be visualised easily and others cannot.