🚀 go-pugleaf

In article <9204092247.AA21316@lilac.csd.bldrdoc.gov> I wrote:
   In exercise 3.4 of the TeXbook, Knuth says that there are 128 (now
   256) control sequences of length 2 (including the escapechar) and up
   to 128^2 (now 256^2) of length 3 (if I play with catcodes. I don't see
   how he gets this.  Don't you need to leave at least one character
   whose <catcode> is not equal to 11 to delimit the cs? I thought about
   using \csname ... \endcsname, but you still need an escape char to
   tell TeX that \endcsname is a cs and not part of the name. Anyone got
   an answer?

Thanks to (in the order I received their replies)

Raymond Chen <rjc@math.princeton.edu>, who pointed out that I can
change the escape character to access different control sequences.
(use \ for everything that doesn't have \ in it, use | for everything
with \ and not |, and use ! for everything with \ and |.

David Kastrup <dak@cip-s01.informatik.rwth-aachen.de> has an elegant
solution, noting that I can say \csname \char27 \endcsname.

Andrew Dobrowolski <aed@arbortext.com> replied with a similar answer
to Raymond's.

Thanks all for your prompt responses and your patience with my
simplemindedness.

---Jon