Review of Expanding 10 PRINT by John

== General Comments ==

I'm going to look at both the Expanding 10 Print text and the outline for the Mazes, Maze Walking, Generate and test chapter as a whole.  I was initially confused about the placement of Expanding 10 Print in the Mazes chapter because the opening section is largely about rewriting the Basic program.  However, it does make sense after reading through the outline of the other sections.  I would recommend reordering the sections so that section 5, "What is a Maze" comes first.  

While I think that this would be a useful change overall, I'm specifically suggesting it because I feel like launching into a chapter where we change a fundamental property of the original program - it's scrolling behavior - requires more justification than that we need to do it so the rest of the analysis in this chapter can happen.  That being said, another option might be to add a section that looks at dynamic mazes (or pathfinding in dynamic mazes?) as well.  10 Print doesn't really generate a dynamic maze in the sense that the walls are being reconfigured but it doesn't really generate a static maze either, so maybe a comparison between static, dynamic, and infinite-time-based-static (or whatever we might call 10 Print) would be useful.

This chapter may want to deal with the concepts of maze construction and walking more abstractly than the Expanding 10 Print section does now, using BASIC as a touchstone but dealing more with the algorithms and processes than attempting to explain the code itself since it is currently placed before the BASIC chapter.  It looks like this is intended for at least some of the other sections outlined, but I would suggest extending it to the current section as well.

== On the Expanding 10 Print section specifically ==

- The description of motion in para 2 is a bit confusing.  Recommend replacing it with the already suggested sequence of screenshots that are just captioned in a callout.

- If it is not done in a preceding section, there should be some discussion that justifies making the maze static.

- Explaining FOR/NEXT is useful, but since it is a fundamental language construct it may fit better in the BASIC chapter (it may be that explaining FOR/NEXT and GOTO near each other help both explanations since GOTO in 10 Print is effectively FOR X = 1 to Infinity).  It should still be ok to use FOR/NEXT to modify the program here even if it is explained elsewhere.

- A discussion about what the interpreter is-as opposed to the language itself-is needed before this chapter since "the interpreter" is referenced repeatedly.  Alternatively, it may be alright to leave details like what is done internally by the interpreter out of this section.