[texhax] symbol for triple vertical 'x'

[Robin Fairbairns]

> The % signs are necessary because after `}' in horizontal
> mode TeX is in mid-line mode where it converts the
> end-of-line character to a token for character 32 (` ') of
> category 10 (space).  After that it enters state S (skipping
> blanks) and ignores any further end-of-lines. (See The
> TeXbook, p. 47.)

not quite.

in state "s", a further end of line character is converted to a \par
token, and things start again.