Method _merge

lib/util/LazySet.js:87–92

* Materializes all deferred additions into the backing set.

()

	 * Materializes all deferred additions into the backing set.
	 */
	_merge() {
		this._flatten();
		merge(this._set, this._toMerge);
		this._toMerge.clear();
		this._needMerge = false;
	}

	/**
	 * Reports whether the set is empty without forcing a full merge.