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Comment by aikah | Hacker News Reader

> I don't think most people working on Node want a Rails equivalent

It wouldn't really be possible anyway. Async programming is hard and the shortcuts one can take with synchronous Ruby are impossible with Async Javascript. Nodejs has a "fibers" lib though , but it doesn't look like it is widely popular, but AFAIK it is the only to truly abstract async programming.

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Try bluebird's Promise.coroutine, I use it everywhere and it works great.

https://github.com/petkaantonov/bluebird/blob/master/API.md#...

Or if you want to use native promises, I threw this together

https://github.com/Dashron/roads-coroutine

ECMAScript 7 has brought true async/await into the language, which currently works in Babel on top of Promises. As far as a regular user is concerned, define a function as "async" and then "await" on the result you're after inside of it. Hardly difficult, in my opinion!

async/await is nice syntax, but it doesn't change the fundamental difference between synchronous and asynchronous code and the viral nature of async functions. Sync functions cannot properly compose async functions in general.

A great essay on this is "What Color is Your Function": http://journal.stuffwithstuff.com/2015/02/01/what-color-is-y...

Using abstractions like http://koajs.com/ and https://github.com/tj/co make Node code feel like every other language.

    var user;
    try {
      user = yield db.insertUser('foo')
    } catch(err) {
      if (err.code === '23505') {
        this.flash['error'] = 'Username taken';
        this.redirect('/register');
        return;
      }
      throw err;
    }

no because you can't write a library which apis are thunks. And your code needs to run in a generator, something you omitted. Fibers are a better alternative , no need for yield and generators everywhere.

Well, I was earnestly sharing run-of-the-mill Koa code since you made async abstractions sound elusive. Didn't realize you just had an agenda.

The thing is that people are actually using Koa/co to solve this problem. I've yet to see someone use fibers as their core webapp control flow abstraction.

What agenda do I have ? I have none, I'm just saying using generators do not abstract async calls. The only way to do that is by using fibers. I'm not pushing for anything, i'm just saying that something like rails couldn't be written in nodejs , (and no sails , is nothing like rails in terms of complexity ).

It's your fiber agenda. My mother used it to try to make me eat my brussels sprouts and I thwarted that, too.

With async functions you interface with everything using promises, it's great.

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