Re: behavior of @math with HTML output

[Jacob Bachmeyer]

Vincent Lefevre wrote:
> On 2022-10-14 11:30:33 +0200, Patrice Dumas wrote:
>   
> > On Fri, Oct 14, 2022 at 12:40:08AM +0200, Vincent Lefevre wrote:
> >     
> > > On 2022-10-13 21:15:57 +0200, Patrice Dumas wrote:
> > > All of them are buggy:
> > >   * Concerning t4h,
> > >       @math{@var{base} \le 16},
> > >     yields "@varbase ≤ 16 ,", so @var doesn't work (while it is needed
> > >     to ensure exactly the same typography/code as outside @math, e.g.
> > >     <var>base</var>) and there is a spurious space before the comma.
> > >       
> > In my experience, t4h is the one that tries harder to use characters
> > for simple math and often succeeds.  Images are still used when it
> > becomes too complex.  It is probably the best for your use.  As you have
> > noticed, however, t4h only knows about TeX, not Texinfo.  It is actually
> > said in the manual that @math should not contain Texinfo commands, in
> > line with the 'recent' better handling of TeX/LaTeX:
> > "In general, the contents of @math or @displaymath should be plain TeX only, with no 
> > interspersed Texinfo commands."
> >     
>
> I assumed that this was for commands that exist in plain TeX, which
> is not the case of @var.
>   

Since "var" actually is a TeX macro (Texinfo works by adjusting TeX's 
configuration to make @ introduce commands, like backslash does in plain 
TeX), would the correct syntax be "@math{\var{base} \le 16}" for the 
example above?

> > In the upcoming version, there is a converter to LaTeX, which allowed to
> > add the customization variable CONVERT_TO_LATEX_IN_MATH.  You could use
> > that in conjunction with HTML_MATH t4h to have Texinfo @-commands
> > produce TeX/LaTeX math in @math.  However, it won't do what you want in
> > term of formatting, as, if I recall well, @var is a no-op in conversion
> > to LaTeX in math mode, as math mode is already slanted.
> >     
>
> Well, math mode normally uses italics, not slanted, but perhaps this
> is changed by t4h (or Texinfo). There is another issue: math mode
> disables kerning (because a sequence of letters typically means that
> this is a product), unless some command is used to specify that this
> is actually text. Not a major issue, but incorrect typography can be
> disturbing.
>   

TeX has an \ifmmode conditional that is true in math mode; @var/\var and 
other marking macros could be adjusted to mark their arguments 
appropriately when invoked in math mode.  Are there other macros that 
would be appropriate in @math?  At first glance, @var seems unique here.


-- Jacob