code: function validateOptionsConstraints(optionsConstraints) {
    if (optionsConstraints.within &&
      !(optionsConstraints.within === 'interactive_message' ||
        optionsConstraints.within === 'block_actions' ||
        optionsConstraints.within === 'dialog')
    ) {
      return new TypeError('Within must be \'block_actions\', \'interactive_message\' or \'dialog\'');
    }
  
    // We don't need to validate unfurl, we'll just cooerce it to a boolean
    return false;
  }
docs: Validates properties of a matching constraints object specific to registering an options request
  @param {Object} matchingConstraints - object describing the constraints on a callback
  @returns {Error|false} - a false value represents successful validation, otherwise an error to
  describe why validation failed.
  @private