Implement ember concurrency examples

[BlueCutOfficial]

Hey @paoloricciuti, these are just a few tests I've done to see what I could do with the lib, I left a few comments to discuss.
Also, it would be interesting to know if there are just different / easier ways to do this with Svelte.

[BlueCutOfficial]

I’ve been playing with svelte-concurrency and I encounter something a bit counter-intuitive with the task arguments. As it is on main, it seems that TArgs has to be an array. I didn’t follow all the threads about TypeScript constraints, but in the main page example, when you do:

const parent = task(async function* (param: number) {
   (...)
   return param * 2;
});

Let’s assume you think you have param === 4, you actually have param === [4] and do:

[4] * 2

Surprisingly it works because you can multiply values in arrays in JS, but in my "accelerating buttons" case I had 0 + [1] that resulted to a string "01".

...args: unknown[] is not a proposal, it's just my lazy fix to get it work =p

[paoloricciuti]

Ok this is actually something else: basically this TS code is inferring the type of TArgs. If you don't pass any parameter it will actually be undefined and when you call perfom this type will disallow you to pass any values. But if you pass some argument then the arguments will be the same arguments that you expect in the task function. It doesn't need to be an array, you can pass a single value and ts will infer that you want that kind of value and force you to use the same value in perform. So basically you can do this

const my_task = task((value: number)=>{
    console.log(value);
});

my_task.perform(4);

[BlueCutOfficial]

I am not sure if I understand how signal is supposed to be used:

In my race case, I wanted a parent task that triggers 3 children tasks, and as soon as one of the children is done, everyone stops.

I couldn't figure out how / when onDestroy is supposed to be called, and I couldn't use cancel because it's kind of an "auto-cancellation", the parent task says in its own body "I am done, I stop all my children". I didn't see how to use the main branch's API to do that, I just wanted a way to run .abort() for the current function.

Considering everything you've already done in the task logic, what do you think is the cleanest way to achieve that?

[paoloricciuti]

Yeah we didn't implement that kind of concurrency yet. Probably i would just do something like

child.perform().then(()=>{
    child2.cancel();
    child3.cancel();
});
child2.perform().then(()=>{
    child.cancel();
    child3.cancel();
});
child3.perform().then(()=>{
    child.cancel();
    child2.cancel();
});

[BlueCutOfficial]

I added this button to check the <progress> elements have their values updated on click, and that works. But my progress update in the different children's tasks has no effect, there might be something I need to learn about the render or for loop maybe?

[paoloricciuti]

I think you just need to call await tick(); after you update the value in the while loop.