[P.6] copyedit: Move a comment for consistency, change "a" to "the", and fix a typo: "f" to "f2"

[mfwitten]

This is a merge commit to bundle trivial changes:

* [This Commit]
|\
| * trivial: s/a/the/
| * trivial: Move a code comment (//...) to the line above the code
| * trivial: s/f/f2/
|/
* d40a490d485a647172eb8e615f293b525de68b7d

[mfwitten]

I force-pushed a new set of commits, so as to make 2 changes:

• Rebase onto latest master.
• Add [P.6] and (#2288) to the subject line of each commit.

[hsutter]

Editors call: Thanks!

[hsutter]

Note to editors: At first I was going to keep the comment on the same line as formatted originally, and then I saw that this change makes the formatting consistent with the immediately preceding example which also puts the comment on a separate line.