code: func (c *Connection) isCapable(featureName string) bool {
  	capabilities, _ := c.Properties["capabilities"].(Table)
  	hasFeature, _ := capabilities[featureName].(bool)
  	return hasFeature
  }
docs: // Convenience method to inspect the Connection.Properties["capabilities"]
  // Table for server identified capabilities like "basic.ack" or
  // "confirm.select".