Thoughts from porting the More tutorial

[samth]

I've updated my port of the "More: Systems Programming in Racket" tutorial; you can see the results here: https://github.com/samth/rhombus-more/

I'm pretty happy with the first version. The major issues are that it uses a lot of @samdphillips's compat libraries that will eventually be needed in the rhombus standard library, and that the methods there are essentially static-only and thus need more annotations than you'd want in a first tutorial. Those problems will go away with more development of the standard library.

The second version exposed a few more small issues, most significantly that there's no room in the indexing syntax for a failure value or thunk as in hash-ref. I should also revive my work on integrating fancy-app-style function syntax (mflatt/shrubbery-rhombus-0#4).

The third version doesn't really change much over the second version.

Overall, my thoughts are:

• Rhombus is progressing nicely. Most of the annoying things from doing this 6 months ago have improved.
• Figuring out how to make interop with Racket smoother will be an important challenge as long as we want to use lots of existing Racket libraries.