Re: parsing of emphasis versus links

[John Kitchin <jkitchin@andrew.cmu.edu>]

I can not reproduce all the things you report.

I think part of the problem is [calc:]. I have to have at least two
characters of path to get a link that is colored.

Eric S Fraga writes:

> Hello,
>
> I have been playing with using embedded calc equations in org mode.  I
> have tried filters and with org emphasis markers but finally have come
> around to using the new org link capabilities.  Thank you John for
> these!
>
> I've defined the following:
>
> #+begin_src emacs-lisp
>   (org-link-set-parameters
>    "calc"
>    :export (lambda (path desc backend)
>              (cond
>               ((eq 'latex backend)
>                (format "\\texttt{%s}" desc))))
>    :face '(:foreground "chartreuse"))
> #+end_src
>
> which I then use like this:
>
> #+begin_src org
>   [[calc:][Pv := 10^(6.886 - 1175.817 / (100 + 224.867)) => 1847.653]]
> #+end_src
>
> and with appropriate settings for calc [1], calc can manipulate and
> evaluate the expressions.  So far, so good.
>
> Two minor issues:
>
> 1. the fontification doesn't colour the links in the colour I would like
>    (chartreuse, #7fff00).

I get partial chartreuse, but there are some fontlock that can go on
top, e.g. if it looks like a latex fragment.

>
> 2. if I have two expressions close enough, both with := and =>
>    operators, org seems to get confused and interprets two of the =
>    symbols, each from one expression, as emphasis markers, as in this
>    example:
>
>    #+begin_src org
>      [[calc:][y := 3 x - 5 => 55]] [[calc:][z := sqrt(y) => 7.416]]
>    #+end_src

I can reproduce the issue above, but I have no way to help improve it.
This particular case looks like emphasis from a simple regexp pov.
Fixing it might require checking that the start/end are in the
same org-element maybe.

>
> Screenshot attached showing both problems: colour and second = sign
> disappearing in first link and first = sign in second link.
>
> Any suggestions on how to improve/fix these aspects?  Both are minor
> presentation issues and everything else is working very well.  Calc
> allows me to work with these expressions easily in org now!
>
> Many thanks,
> eric
>
>
> Footnotes:
> [1]  Settings using calc: links:
>
>      #+begin_src emacs-lisp
>        (defun esf/org-mode-calc-settings ()
>          (setq calc-embedded-open-formula "\\[\\[calc:]\\["
>                calc-embedded-open-new-formula "[[calc:]["
>                calc-embedded-close-formula "]]"
>                calc-embedded-close-new-formula "]]"))
>        (add-hook 'org-mode-hook #'esf/org-mode-calc-settings)
>      #+end_src


--
Professor John Kitchin
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@johnkitchin
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