Immutable-js: Set difference on Maps

[derekdreery]

It would be very useful for me to have set difference operations on Maps as well as sets. For example something like

const map = Immutable.Map({a: 1, b: 2, c: 3});
const set = Immutable.Set([a, b]);
console.log(map.subtract(set)).toJS(); // prints {c: 3}

[udnisap]

i can help out if this is not done yet

[umidbekk]

See Map#deleteAll (I guess #895 not published yet)

const map = Immutable.Map({a: 1, b: 2, c: 3});
console.log(map.deleteAll(['a', 'b'])).toJS(); // prints {c: 3}
console.log(map.deleteAll(Set.of(['a', 'b']))).toJS(); // prints {c: 3}
console.log(map.deleteAll(List.of(['a', 'b']))).toJS(); // prints {c: 3}