aversal over a data structure.
Also allow for callbacks before and after visiting the children
of a node. Also allow for a custom `get-children` function to
change traversal as needed. Will detect cycles if an empty table
is passed as the `seen` parameter, which is used to cache values
that have been visited.</pre></div><hr><div class="binding"><span id="misc/do-def" class="binding-sym">misc/do-def</span> <span class="binding-type">macro</span> <span class="binding-type"><a href="https://github.com/janet-la