Re: [Texmacs-dev] Math codes

[Joris van der Hoeven]

Hi Todd,

On Sat, Apr 21, 2007 at 04:50:19PM -0400, Todd Wilson wrote:
> I sent the message quoted below to texmacs-users without any response. 
> However, instead of just resending it here, I want to ask a different 
> question.  I've skimmed through the source code and have found it quite 
> well-organized and readable, and I might have some time coming up that I 
> could use to contribute to the development myself.  Can someone outline 
> what I would have to do to *add* math codes to TeXmacs (which I assume 
> it doesn't already have)?  I found the file
> 
>     /usr/share/TeXmacs/langs/mathematical/syntax/texmath.syx
> 
> which already seems to have most of what I would need in place;  I'd 
> just need to introduce something that could change the Type (or Class?) 
> of a symbol so that it would be rendered appropriately.  I'm guessing 
> something like
> 
>     <as-class|(class)|(character)>  or  <as-type|(type)|(character)>
> 
> Any ideas?

In this form, this would require some hacking of the C++ code
(so as to retrieve the classes from texmacs.syx).
Alternatively, one might simply define a few macros "mathord",
"mathbin", etc. with the correct presentation for different types.

Notice that operator types are not very well implemented in TeXmacs:
I really should compute spacing as a function of the operator types
of the left and right hand sides. As long as this is not done (in C++),
the macro-solution is sufficient.

> >Is there in TeXmacs an equivalent of TeX's \mathord, \mathbin,
> >\mathrel, etc.?  There are times when TeXmacs's default spacing in
> >formulas is not correct.  For example, when using ":" as a binary
> >relation, as in typing judgments, I'd like to use it as a \mathord in
> >declarations on the left of the turnstile and in quantifiers and
> >lambda abstractions, and use it as a \mathrel on the right of the
> >turnstile.

Another interesting idea (already used occasionally) is to define
different TeXmacs symbols for the same glyphs. You might have
a normal ":" and additional symbols "semicolon", "oftype", etc.
with different types.

Best wishes, Joris