SVG StyleList unused styles?

[Peter Krautzberger]

The styles for the SVG output include .mjx-dashed and .mjx-dotted:

MathJax-src/ts/output/svg/Wrappers/mtable.ts

Lines 113 to 119 in 2911de7

 'g[data-mml-node="mtable"] > .mjx-dashed, svg[data-table] > g > .mjx-dashed': { 
   'stroke-dasharray': '140' 
 }, 
 'g[data-mml-node="mtable"] > .mjx-dotted, svg[data-table] > g > .mjx-dotted': { 
   'stroke-linecap': 'round', 
   'stroke-dasharray': '0,140' 
 }, 

Since I couldn't find any content with either class on the AMS end, I looked where these classes might get added - and didn't find anything. It looks like addBorderBroken does the job of handling these borders.

MathJax-src/ts/output/svg/Wrapper.ts

Lines 272 to 274 in f939f2f

 if (style[i] === 'dashed' || style[i] === 'dotted') { 
   this.addBorderBroken(path, color[i], style[i], width[i], i); 
 } else { 

Perhaps the classes are leftovers from v2 or there was a later change or (more likely) I didn't spot where these classes are actually used.

[Davide P. Cervone]

These are used for the lines within a matrix (from the rowlines and columnlines attributes of mtable), and are created in the lineClass() function

MathJax-src/ts/output/svg/Wrappers/mtable.ts

Lines 241 to 243 in 8565f9d

 protected lineClass(style: string): string { 
   return CLASSPREFIX + style; 
 } 

It constructs the class name dynamically, which is why searching for mjx-dashed or mjx-dotted won't find it.

This method is used in the makeFrame(), makeVLine(), and makeHLine() methods that follow it.

[Peter Krautzberger]

Thanks for clarifying!

[Peter Krautzberger]

Just to follow up and more FYI.

Looking at lineClass, I noticed (from AMS content) that this generates one class name (mjx-solid) that has no declaration in StyleList. So IIUC since authors could specify random attributes, this generates random class names, but only dotted and dashed do anything. I guess that's nice for authors who want to add custom styles.

This reminds me that in AMS content I found that the complex selectors in StyleList never matter (to the content), except for the overflow related one (which we actually replace with a helper class). Now it looks there's also always a class; that's nice (unless mjx-solid is likely to be removed).

I also noticed that data-line has two different attribute values that are never used (and data-frame doesn't really need "true" either). So switching to mjx-solid offers additional opportunities to clean up bloat in post - which is nice.

I realize I'm playing with fire but for SVG this has worked out well over the past few years.