$toggle support for Sets

[mnpenner]

For lists of checkboxes like this:

I like to store the IDs of the checked elements in a Set.

To "toggle" a checkbox right now I have to do this:

checkOccasion = id => ev => {
    const spec = {
        enabled: {
            [ev.target.checked ? '$add' : '$remove']: [id],
        }
    };
    this::updateState(spec);
}

<CheckboxLabel value={occ.id} checked={enabled.has(occ.id)} onChange={this.checkOccasion(occ.id)}>{occ.name}</CheckboxLabel>

Would be nicer if instead I could just do:

const spec = {
    enabled: {
        $toggle: [id],
    }
};

i.e. enabled is a Set, so if id is already contained in the set, it would be removed, otherwise it would be added.

---

Actually, alternatively $toggle could accept an object [too] which would explicitly let you add or remove specific elements:

const spec = {
    enabled: {
        $toggle: {
            [id]: ev.target.checked
        },
    }
};

That'd let us skip the .has check too.

[linq2js]

this suppots toogle on many props https://www.npmjs.com/package/immhelper