4 ms·

What concurrency in Node.js could have been

5 points by erjiang 12y ago

bjouhier 12y ago
The point about fibers is incorrect. I posted a detailed comment on your blog.
mattkrea 12y ago
So since it seems to me that this article entirely failed to mention why the callback pattern was harmful could someone else?
- erjiang 12y ago
  I've described some in the post I linked at the beginning, and many many others have described similar things. I've cribbed these from TJ Holowaychuk's recent post and added some others: * callbacks are not logical for expressing sequential logic * you end up with deeply nested code when having many sequential actions * you may get duplicate callbacks * you may not get a callback at all (lost in limbo) * you may get out-of-band errors * emitters may get multiple “error” events * missing “error” events sends everything to hell * often unsure what requires “error” handlers * “error” handlers are very verbose * callbacks suck * too many different libraries to "fix" callbacks that each have their own problems * e.g. easy to lose errors in Q promises * varying performance of various promises/async libraries * "best" async library constantly changes * callback style is the only common api, so you end up with wrappers for each library x library combination * sometimes forget whether a function uses a callback, returns a promise, is a generator, returns a stream, returns something that looks like a promise * some libraries may not call callback asynchronously and more. Callbacks have gotten a reputation as a dead horse that people like to beat on.
yortus 12y ago
Using asyncawait (https://github.com/yortus/asyncawait https://github.com/yortus/asyncawait): var bakeCookies = async (function(cookie_mix) { print("Baking cookies..."); var oven = new Oven(cookie_mix); var cookies = await (oven.bake(15)); // bake for fifteen minutes cookies.decorate(); return cookies; }); It's plain JavaScript, concurrent, and works with plain node.js, unlike StratifiedJS.

5 points by erjiang 12y ago

The point about fibers is incorrect. I posted a detailed comment on your blog.

So since it seems to me that this article entirely failed to mention why the callback pattern was harmful could someone else?

erjiang 12y ago
I've described some in the post I linked at the beginning, and many many others have described similar things. I've cribbed these from TJ Holowaychuk's recent post and added some others: * callbacks are not logical for expressing sequential logic * you end up with deeply nested code when having many sequential actions * you may get duplicate callbacks * you may not get a callback at all (lost in limbo) * you may get out-of-band errors * emitters may get multiple “error” events * missing “error” events sends everything to hell * often unsure what requires “error” handlers * “error” handlers are very verbose * callbacks suck * too many different libraries to "fix" callbacks that each have their own problems * e.g. easy to lose errors in Q promises * varying performance of various promises/async libraries * "best" async library constantly changes * callback style is the only common api, so you end up with wrappers for each library x library combination * sometimes forget whether a function uses a callback, returns a promise, is a generator, returns a stream, returns something that looks like a promise * some libraries may not call callback asynchronously and more. Callbacks have gotten a reputation as a dead horse that people like to beat on.

yortus 12y ago

Using asyncawait (https://github.com/yortus/asyncawait https://github.com/yortus/asyncawait): var bakeCookies = async (function(cookie_mix) { print("Baking cookies..."); var oven = new Oven(cookie_mix); var cookies = await (oven.bake(15)); // bake for fifteen minutes cookies.decorate(); return cookies; }); It's plain JavaScript, concurrent, and works with plain node.js, unlike StratifiedJS.