delete(index, length = 1) {
    if (this.doc !== null) {
      transact(this.doc, transaction => {
        typeListDelete(transaction, this, index, length);
      });
    } else {
      /** @type {Array<any>} */
      this._prelimContent.splice(index, length);
    }
  }
Deletes elements starting from an index.

@param {number} index Index at which to start deleting elements
@param {number} length The number of elements to remove. Defaults to 1.