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In <9207231534.AA00732@auric> cash@auric.uni-koblenz.de (Martin Carstensen) writes:

| The concrete syntax of fuzz differs slightly from the one LaTeX produces
| from specifications (e.g. fuzz syntax contains the string "\forall"
| where LaTeX produces the quantor symbol itself, schemas are more
| complicated examples).

| Recently I tried to define strings like this:

| 	\begin{zed}
| 	LETTER ::= a|b|c|d \\
| 	STRING ::= string \ldata \seq LETTER \rdata
| 	\end{zed}
| 	
| Now I'm looking for a way to tell LaTeX what strings shall look like
| and which will be accepted by fuzz. The following approach would be
| treated properly by fuzz, but the LaTeX definition does only do half 
| of the job.

| 	\newcommand{\str}[1]{"#1"}
| 	%%\begin{zed}
| 	%%\str == string
| 	%%\end{zed}

| 	\begin{axdef}
| 	s: STRING
| 	\where
| 	s = string \langle a, b \rangle \\
| 	s = \str {\langle a, b \rangle}
| 	\end{axdef}

I am not sure your solution works at all for the new version of fuzz, at
least we have had troubles with spurious {..} pairs.

Anyway, you need to appeal to a little TeX (i.e. use \def rather than
\newcommand). In general if you want to produce a novel concrete syntax
for a function application use a TeX definition like

\def\f(#1){...}

Now you can write \f(arg) in your Z, get fuzz to accept it, and get
LaTeX to print it any old how. (This idea was suggested by Mike Spivey)

I your case you need to redefine the TeX output of \langle .. \rangle.
Try this:

\def\str(#1){\def\langle{\mathopen{\mbox{``}}}\def\langle{\mathopen{\mbox{``}}}#1}

You list now appears within quotes rather than < .. > brackets.

I am not as clear on how to get rid of the commas. Some trick with a
\mathchardef or \mathcode I suppose. I don't think you can trick fuzz
into accepting some character other than the comma. Find a copy of the
TeXbook.
--
When soldiers form lines or hollow squares, you call it reason.
When wild geese in flight take the form of a letter V, you say instinct.
When the homogeneous atoms of a mineral arrange themselves into shapes
mathematically perfect you have nothing to say. You have not even invented a name to conceal your heroic unreason."