Support ^superscript^ ~subscript~ and ==highlight==

[tomidery]

I'm using Discount in a simple content server to render Markdown files to HTML. I tried to make it fully server side solution without using javascript on the client side. The Markdown pages are authored using Typora. I found that Discount is not 100% compatible with the editor:

• superscript in Typora (and actually other Markdown implementations) expect ^ to be used before and after the text, e.g. x^2^
• superscript in Typora does not expect the brackets ()
• Discount does not support subscript e.g. H2O
• Discount does not support ==highlighting text==
  There are more differences, and Typora also lacks some of Discount's features, but I wanted at least to implemented these 3 listed above.

You will find my attempt in this pull request. I would like to hear your comments and whether you consider accepting my changes.

Note that all 3 formatting features respond to the single configuration flag which was initially used only for superscript.

[Orc]

Can you redo this feature request by surrounding the changes with #ifdefs? eg:

#ifdef TYPORA
... your feature ...
#else /* !TYPORA */
... my feature ...
#endif /*TYPORA*/

This is because this is a moderately large change from current behavior and if it's intended to be a backend for typora I'd prefer that it be build specifically as a backend for typora.

[tomidery]

Sure, I can rewrite it. Do you mean all 3 changes ^ ~ and == ? or only the superscript? For the highlight I hardcoded the colour in the HTML tag itself as I wasn't sure if you have any CSS in place which I could extend. Are you OK that all 3 features are enabled with a single configuration flag? Cheers, Piotr P.S. I think this syntax is used also by other tools, not only Typora

…

On Wed, May 12, 2021 at 5:38 PM Orc ***@***.***> wrote: Can you redo this feature request by surrounding the changes with #ifdefs? eg: #ifdef TYPORA ... your feature ... #else /* !TYPORA */ ... my feature ... #endif /*TYPORA*/ This is because this is a moderately large change from current behavior and if it's intended to be a backend for typora I'd prefer that it be build specifically as a backend for typora. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#238 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AK42NEOQSAD4V7ZIGBKBKLTTNKOGRANCNFSM43NIX44Q> .

[baltitenger]

@tomidery In other tools, ==text== results in <mark>text</mark>, which is better than hardcoding a background color in my opinion.

[tomidery]

I updated the code in this PR to include the conditional compilation for x^y syntax and used for highlights.