.length == 1 at all times

[michal-minich]

var = SArray([]);
console.log(arr.length); // 1
arr.push("abc");
console.log(arr.length); // 1

Solution would be probably to fix the returned number or remove the .length accessor.

[michal-minich]

I just noticed this .length is not part of interface and comes from Function prototype. Given that SArray represent array-like object this is very confusing. I expected the length to return count of elements. Especially IDE allowed me to write it, and there are other array-like functions like .map.

Can the SArray be not based on function prototype or override the length behavior?

[adamhaile]

S (and by extension SArray) is not a proxy-based reactive library, i.e. the goal is not to reproduce the exact same interface as a plain JS object and have it be reactive "magically." S is based on first-class reactive containers, 'signals', which are represented as functions and must be explicitly unwrapped -- signal() -- to obtain the current value. So if you want the length of the array carried by a signal, you'd do array().length.

If you're looking for the proxy behavior, you might want to check out Solid, which uses the S reactive engine internally (and interops with S code) but with proxy-based access.

[michal-minich]

The issue I have with the .length, that it was confusing. Since some of array operations were available, I assumed the length was too. It was quite easy to find during app testing that it is not working as I expected. But from me, as a user, it really looks like a bug in SArray. I have experience mostly with typed languages, so I rely on code completion and compiler to suggest and accept something. Probably just modifying the TypeScript return type on the SArray can limit miss-usage of .length (since the fact that SArray is prototype of Function is implementation detail, so cast to access .length would be appropriate usage in TS).

Thank you.

[beenotung]

This can be easily patched nowaday. Thanks to the progress Javascript spec has made in the meanwhile.

let xs = SArray([] as any[]);

Object.defineProperty(xs, 'length', {
  get(): any {
    return xs().length;
  },
});

S(() => console.log('length:', xs.length)); // reports 0,1,2

console.log('xs.length', xs.length); // 0
xs.push(1);
console.log('xs.length', xs.length); // 1
xs.push(1);
console.log('xs.length', xs.length); // 2

[Qix-]

Just use the get keyword...

const foo = {
    get length() { return this().length; }
};

Something to that effect.