lib/asyncflow.js
function Flow(limit) {
  this.limit = limit;
  Object.defineProperty(this, "futureStack_", {
    enumerable: false,
    writable: true,
    value: []
  });
  Object.defineProperty(this, "runningNum_", {
    enumerable: false,
    writable: true,
    value: 0
  });
}
function Flow(limit) {
  this.limit = limit;
  Object.defineProperty(this, "futureStack_", {
    enumerable: false,
    writable: true,
    value: []
  });
  Object.defineProperty(this, "runningNum_", {
    enumerable: false,
    writable: true,
    value: 0
  });
}
Flow class.