mailing-list for TeXmacs Users

[Jan Lellmann <address@hidden>]

Hello Joris,

I remember struggling quite often with this behavior, however I don't recall 
on which expressions exactly :/

I think it was mostly in equations of the form

  x y z,(extra space) (forall) a in b,

where it is very natural to type a space. I can see how the "space + comma" 
shortcut makes sense, however it could be a bit confusing to new users, 
since it is a shortcut they will almost certainly activate unintentionally. 
Maybe it would make sense to add a first-time warning dialog explaining such 
behavior.

Jan

On 30.09.2011 07:36, Joris van der Hoeven wrote:
> On Sun, Jun 26, 2011 at 04:44:44PM +0200, Jan Lellmann wrote:
> > I noticed that recent versions of Texmacs exhibit a strange
> > behavior: When I type a comma "," in an equation followed by space,
> > the comma disappears. This is quite annoying. Is it intended
> > behavior, and if yes, why?
>
> Yes, this is the intended behaviour.
> The shortcut ", " stands for an invisible comma.
> For instance, "a_i, j" allows you to type the matrix entry $a_{ij}$.
>
> In math mode, users are not intended to manually enter spaces
> around commas or other operators, except if you want to explicitly
> apply a function. The typesetter knows about the amount of whitespace
> to put around commas and operators. In other words, type "f(x,y)"
> and not "f(x, y)"; also type "x+y", not "x + y".
>
> I agree though that the behaviour may seem unnatural;
> maybe I should only activate it in semantic editing mode.
> On the other hand, it is true that spurious commas are
> *THE* major nuisance to parsing math formulas.
> It is really a nasty habit. An alternative would be
> to simply ignore such spaces.
>
> On this occasion, I would re-ask users to try the semantic
> mathematical editing mode (see explantions in the documentation
> on typing mathematical formulas); it remains useful to have
> more feedback on this issue.
>
> Best, --Joris