Function intersection

external/.d3.js:1325–1337

(values, ...others)

}

function intersection(values, ...others) {
  values = new InternSet(values);
  others = others.map(set$2);
  out: for (const value of values) {
    for (const other of others) {
      if (!other.has(value)) {
        values.delete(value);
        continue out;
      }
    }
  }
  return values;
}

function set$2(values) {
  return values instanceof InternSet ? values : new InternSet(values);