What’s wrong with generators?
I recently gave a talk where this question came up: https://youtu.be/uRbqLGj_6mI?t=2166
I’ve also imposed generators on a lot of colleagues.
I think they are mostly misunderstood and potentially in the realm of being “magical” — at least on the surface.
The reality is they are syntactic sugar on top of functions with recursive switch statements where each case is a yield point.
They aren’t that hard to grok — the syntax is mind bending. Having code that looks synchronous but behaves asynchronous is “magical.”
I think it does come down to that because everyone loves async/await even tho that’s just sugar on generators where each yield must be a promise.
I'm also in the process of rebuilding redux-saga but without the redux part: https://github.com/neurosnap/starfx
It's still in alpha stage, but it is very reminiscent of redux-saga.
Generators were introduced during JavaScript’s awkward adolescence, where the cutting edge of ES6 was only possible through Babel (which was then called 6to5). They’re fantastic for turning array like classes into iterable collections. But that’s not what makes them bad.
For a time you had a perfect storm of JavaScript Hell. Promises were polyfilled and rewritten as generators to take advantage of the `yield` keyword. You’ll most likely find out about this trick at the least opportune time: while debugging an async redux action. Now every single stack trace is a high-stakes game of “detangle the Christmas lights!
This was truly a horrible time to be a front end developer. Not only did you have to transpile your code, you had to debug it through a source map wrung through Webpack’s module system. And while you’re picking through this mud ball of a web app, there’s a Super Senior Software Engineer giving a talk on the virtues of observable data management!
I’ve always suspected that these galaxy brain engineers are more like window washers on an ivory tower. And as for the rest of us, we’re just the code gnomes who are shrug when given triangular bricks until told how round bricks are actually better.
I know this is all hyperbole but the emotion is real. For every productive hour of work gained through a new and necessary features, engineers have lost 10-fold on the lesser well-thought out JavaScript. I’m not so sure that native observables will be any different.