Ideas for refining the structure of FFTrees objects

[ndphillips]

@hneth In the context of #224 I realized that the structure of FFTrees objects is making development challenging - such as knowing how to modularize the plot.FFTrees() function.

The current code to create FFTrees objects is contained here: https://github.com/ndphillips/FFTrees/blob/71b9da041d16439f7de3091f7aa5987885f45108/R/fftrees_create.R#L765-L852

Here are the core issues I see:

• Inconsistent and confusing naming
  • Ex) How do the definitions, inwords, stats, level_stats, and decisions objects in FFTrees.relate to each other?
• Information at different levels of abstraction aren't consistently stored
  • Ex) Why are tree definitions stored at the tree level but not the node level? Why aren't overall tree accuracy stats located close to the tree level accuracy stats?
• Inconsistent storage locations
  • Ex) Why are criterion_name, cue_names and formula stored at the same level as trees, data and params? Could these be stored in a list such as metadata?

To solve these issues, I'm drafted an object design doc at https://github.com/ndphillips/FFTrees/wiki/%5B80%25%5D-FFTrees-Object-Design. I'm eager for feedback

[hneth]

Just realized that my comment on #224 should better have been posted here — sorry!

[ndphillips]

No worries, let's carry on the discussion here