Thank you for this! ( and for NOT this LOL ) I am about to start in a big coding project in Observable and your notebook is perfect for me to use.

+backwards compatible. You can add parameters without breaking legacy call sites

Are there good example uses that can be looked at? Is there a name to this design pattern so it can be searched online?

I just got the idea from the sources above. It does appeal to me and lingers in the back of my head, ready to use whenever beneficial. Haven’t seen a lot of the Object.freeze, though. The constructor example above is used all over the ES place, TMO, some more in disguise. Pattern name? Well, it’s an object factory, using prototypal inheritance. So, some kind of object plant or mill, to distinguish its name from the factory name. protoplant? Has a nice ring to it. protomixer? mixerplant?