Clojurians Log v2

Can you elaborate on the transition function?

I'm not hugely up on it, but it seems to add and remove classes based on timeouts. Right now it's wrapping the children in a div which has these applied when necessary, which of course can do things like setting up new stacking contexts.

basically we use it to swoosh things on and off the page

I'm afraid I still don't get the problem at all. What prevents you from just passing the right classes down to children? How would using metadata solve anything?

it's used to wrap a bunch of components, and IIUC we don't want to modify every single one to accept classes. (But yeah… that's probably the right way to go.)

I see. Metadata cannot work here because it would require either magically passing className all the way down to React elements that result in DOM nodes, or modifying the DOM tree after it has been rendered. Yes, passing the classes around is the way to go. Alternatively, there are styling systems, CSS-in-JS. In at least some, you can define a particular class for a component, pass it down or hard-code it, and override what the class means at run time. But a huge overkill just for this task if you don't already use something like that.

all makes sense. Thank you 🙏

It might seem absurd to modify the hiccup after a subroutine has composed it, but Clojure(Script) is super for data processing and hiccup is just data.

That would require turning children components' hiccup into function calls.