Clearer argument name for Reveal.js highlighting with `code-line-numbers`

[malcolmbarrett]

code-line-numbers is an unclear name for using with Reveal.js to do highlighting, particularly since code-line-numbers does other important things to the output. IMO this deserves its own argument, e.g. code-line-highlighting, or at least an alias along those lines

[mine-cetinkaya-rundel]

Just chiming in to say I like the idea of giving this a different name!

[cderv]

Just adding a bit of context regarding why this name

code-line-numbers is not specific to revealjs format. This is the configuration to trigger Pandoc to add numbered line to code chunk. This is used in html format for example.

In bare Pandoc, this is with .number-line class on chunk (Pandoc Manual)

Revealjs has a feature to highlight lines but for Highlight.js and the idea was to port this feature in Quarto to work with Pandoc syntax highlighter. Though in Revealjs, the feature is triggered by adding data-line-numbers to code part.

This is the reason why when we added the feature in #147, we thought that reusing the code-line-numbers used in other format to add line numbers to revealjs with the specific addition of highlighting was better than adding a new specific option like code-line-highlighting specific to revealjs format

I am not against adding a new options but this means there will be two options

• code-line-numbers which is TRUE by default for revealjs format
• code-line-highlighting which will be unset by default, and used only for revealjs special feature
• If code-line-numbers is FALSE, then code-line-highlighting would have no effect (or takes precedence - choice to make).

Hopefully this clarify the initial choice of keeping the same option name, while adding the feature.

[cderv]

From a discussion with the team, idea to add also code-line-numbers-start instead of startFrom and this for all format, not just revealjs.

And also proposal for new name: code-line-numbers-highlight