d3js Advisory
In case you have, like me, played around with older versions of d3 and wondered why calls to load data in v5 don't seem to work, please do the smart thing instead of struggling all afternoon like I did.
Smart Thing
- Read the CHANGES page
/Smart Thing
To wit, Mike Bostock and team have this to say:
D3 now uses Promises instead of asynchronous callbacks to load data. Promises simplify the structure of asynchronous code, especially in modern browsers that support async and await. (See this introduction to promises on Observable.)
Hope this saves you a bunch of time one random coding session a few months from today when you're just about to start pulling your hair out in frustration.