Tim's issues

[ranjitjhala]

1. the bizarre length --> len suggestion
2. what is (!) in chapter 4
3. chapter 4 is too sudden:
   • what is a measure exactly
   • rapid introduction of "accumulator" loops e.g. vector sum/ higher-order functions
   • specifically Inference: Our First Recursive Function (is complex because it uses an accumulator)
   • then the HOF examples are very complex (and should be explained later after EASY HOFs)
4. solve 3 by writing a small "measures" chapter between 3 and 4 which has lists, len, average, simple recursive functions on lists etc. basically -- convert chapter 3 of lh-workshop into a simpler intermediate chapter with: (a) data types, (b) measures, (c) no recursion -- year, CSV (d) simple data-oriented recursion (e.g. map, append)
5. The "measure" / Sec 2.6 bit in chapter 2 seems out of place, not really motivated well. Perhaps put into the 4 above and it would fit nicely.
6. When you DO get into go style recursion with accumulators -- it is actually complex if the person has not seen it before, so more explanation there is helpful.
7. Make clear what exactly is a DEFINITION (as in: enclose in a BOX explicitly marked as DEFINITION -- we are introducing a new keyword) e.g. "specification" (Ch 3 -- what IS a specification), or "verification" or "measures" (ch 4) or "assumes" -- when each such idea is introduced, mark it clearly as a new concept and give concrete examples.
8. Perhaps reuse the "RefTypes = Types + Predicates" as the motif for introducing a new notion.
9. For the more interesting examples -- have more discussion about
   • the right answer/ solution key
   • the other approaches
   • perhaps hidden behind a 'click here to discuss'
   • A nice example is the text around Exercise: (Vector Head) -- more of that would be valuable. +At the least, some solution to compare against.