% Answers for galley proofs:

\ansno X.0:
 According to the index, |\|\] is primitive but
|\|\<return> isn't. The command `|\def\↑↑M{\ }|' in
Appendix~B is what actually defines |\|\<return>, since a
return is representable as |↑↑M|. Asking \TeX\ to |\show\↑↑M|
\looseness-1
produces the response `|>| |\↑↑M=macro:->\|\]|.|'.