Hierarchical Bitset for efficient iteration and boolean operations on sparse data. This is a translation to js of the amazing hibitset.

import * as B from "hibitset-js";
const set = new B.BitSet(0);
for(var i = 0; i < 1000; i += 1) {
    expect(set.add(i)).toBeFalsy();
    expect(set.add(i)).toBeTruthy();
}
for(var i = 0; i < 1000; i += 1) {
    expect(set.contains(i)).toBeTruthy();
}

const B.xor(set, B.zero(set.size()));

function iterate(a: B.HierarchicalBitset, callback: (value: object) => void) {
  const iterator = B.createIterator(a);
  while(true) {
    const { value, done } = iterator.next();
    if(done) {
      break;
    }
    callback(value);
  };
}

the first part is an excerpt from the tests. Then a boolean operation and the zero factory method are demonstrated. The iterate function showcases how to iterate over a BitSet. The iterate and createIterator functions are part of the library. The HierarchicalBitset type is an interface shared by all BitSets.

Hierarchical Bitsets are extremely useful to iterate over sparse data structures.

checkout the project and

npm install && npm test

jest --watch

MIT.