code: func WithExtractFailurePolicy(p ExtractFailurePolicy) TracerOption {
  	return func(o *Tracer) error {
  		if p < 0 || p > ExtractFailurePolicyTagAndRestart {
  			return ErrInvalidExtractFailurePolicy
  		}
  		o.extractFailurePolicy = p
  		return nil
  	}
  }
docs: // WithExtractFailurePolicy allows one to set the ExtractFailurePolicy.