lib/j2119/role_finder.js
function mapOfMaps () {
  const m = new Map()
  m.getOrCreate = function (key) {
    if (!this.has(key)) this.set(key, mapOfMaps())
    return this.get(key)
  }
  return m
}
function mapOfMaps () {
  const m = new Map()
  m.getOrCreate = function (key) {
    if (!this.has(key)) this.set(key, mapOfMaps())
    return this.get(key)
  }
  return m
}
descendantRoles