While this will be used for the OwnedLiterals since they must always exhibit the original DustJS behavior, I am going to keep exposing separate math functions for ContextElement instead of simply requiring them to implement Into<MathNumber> since people might want to implement math in unusual ways with unusual types.
The permutations are pretty intense, so I think I'm going to do the same design I did for comparison where I have a JsonNumber (but I'll call this one MathNumber and rename JsonNumber to ComparisonNumber), convert the types to that, and then do the math.
Since I'm changing a pretty core concept of the renderer, I'm going to be rebuilding it piece by piece. In the interest of being able to rapidly change things and check if they are valid through compilation, I need to eliminate most of the old code so I do not have that weighing me down.
Before I was relying on Loopable to both determine truthiness and get a list of elements to loop over. This will no longer work since I need to only set $idx and $len when iterating over actual arrays, as opposed to all truthy values, so I've finally made truthiness explicit.
Need to see if I can do a generic implemented of IntoBoxedContextElement for all objects implementing Copy, and I need to implement the compare code to make sure this all works before I start integrating this more.