Extension classes of Map and Set that do not have size limits.

They actually extend Map and Set so instanceof works and they function in exactly the same way Map and Set do*.

install:

npm install bigbigmapset

use:

import {BigMap, BigSet} from "bigbigmapset";
let m = new BigMap();
let s = new BigSet();

This implementation is also runtime independent. Different javascript runtimes have different size limits on Map and Set but it doesn't matter what those specific size limits are. They could vary within the same runtime and this implementation would still work.

*As of July 28 2025. If new methods are added to Map and Set and this package has not been updated, they will be inherited by BigMap and BigSet but most likely will not work, acting as though the BigMap or BigSet was simply empty (most likely failure mode).