code: func (s StreamName) Concat(o ...StreamName) StreamName {
  	parts := make([]string, len(o)+1)
  	parts[0] = string(s)
  	for i, c := range o {
  		parts[i+1] = string(c)
  	}
  	return StreamName(Construct(parts...))
  }
docs: // Concat constructs a StreamName by concatenating several StreamName components
  // together.