D3 v,3 and v.4 and examples/samples

[jimlyn...@gmail.com]

The number of examples/samples of D3.js graphs and charts is very large. 

There are those on the github/d3/d3/wiki gallery, examples, etc. 

There are those on bl.ocks.org.

I have not worked with D3 since v3. When I moved on, version four had just come out and the concept of modularity was evolving.

My question: have all those examples/samples been updated to version 4, or have been determined to work with version 4? 

Or will D3 become like Python and several versions kept around for pre-existing scripts?