Arrow mark (like link, but with an arrowhead) and swoop mark (like link, but with a curved line).

[Fil]

partially implemented in #38 and
https://observablehq.com/d/c364dd180391294a

[EE2dev]

I thought of arrowhead more to be a constant option for Plot.link() and Plot.line(), with the choice of several arrowhead markers

[tx0c]

partially implemented in #38 and https://observablehq.com/d/c364dd180391294a

#38 (comment)

superseded by plugin https://observablehq.com/@data-workflows/plot-arrow

both links are no longer there, is #39 #38 still in progress? stuck for a whole year

and ideas in #41 for any symbol mark put on the link would be awesome

[Fil]

You should now be able to access the notebook with the suggested plugin at https://observablehq.com/@fil/plot-arrow

I have not worked on arrowhead symbols. Suggestions and contributions are welcome.