ceres is a quite simple set of short, sharp functions showing a means to handle doubly linked lists in a human readable way.
The functions presented here are really no more than just a useful exercise in managing arrays, or to be more precise. a means to map and traverse RDBMS schema representions.
To be fair to the humble array, once nesting (the means to hold arrays within arrays) became common place, the map method was inevitable. Whether it adds, or for that matter simplifies, a great deal towards the art of array manipulation is open to debate.
These functions, although primitive, began life as the basis for handling large JSON lists. The text-based structure of these lists is highly conducive to modelling one to n data representations and these simple routines can be useful when there is a requirement to traverse and manage these purely text based constructs particularly when they contain long cartesian joins.