[texhax] help with identifying some macros

[Donald Arseneau]

"P. R. Stanley" <prstanley at ntlworld.com> writes:

> Here's an example of two of them in use taken from The Z Notation: a
> Reference Manual by Michael Spivey.
> 
> $birthday$:

He should be flogged for that!

> \[

Is this a bit of LaTeX mixed up with ugly Plain TeX?  Or is
it a "Z" macro?

> 	known = \{\,{\rm John, Mike, Susan}\,\} \\

The \rm is better, but I think those words are still in math 
mode.  Horrible!

> \also
> 	birthday = \{\,\vtop{\halign{\strut#\hfil&${}\mapsto{}$#\hfil\cr
> 			John&  25--Mar,\cr
> 			Mike&  20--Dec,\cr
> 			Susan& 20--Dec\,\}.\cr}}
> \]
> Truth be told I've seldom come across anything so cryptic. For example, what
> does the "#" signify?

Look up the meaning and usage of \halign in The TeXbook or in
TeX by Topic; or skip it entirely!  The first line (up to \cr)
of \halign is a template, and # shows where the text of the
following rows is inserted in the template.



-- 
Donald Arseneau                          asnd at triumf.ca