For fans of eager evaluation, there's a VSCode plugin called Quokka that inlines similar functionality as code annotations as you work.

https://quokkajs.com

The youtube channel 'funfunfunction' (@mpj) is where I first learned about the tool.

https://www.youtube.com/watch?v=W4brAobC2Hc (JS iterators explanation using Quokka)

(They started sponsoring his channel several months after he began singing their tool's praises.)