---
title: "The Joy of a Single-Purpose Class: From String Mutation to Message Composition"
url: https://daily.dev/posts/the-joy-of-a-single-purpose-class-from-string-mutation-to-message-composition-3rt6wk2qm
source_url: https://blog.arkency.com/the-joy-of-a-single-purpose-class-from-string-mutation-to-message-composition/
type: article
source: "arkency"
published: 2025-10-30T15:48:02.336Z
updated: 2026-03-15T03:46:13.853Z
tags: ["general-programming", "rails", "ruby"]
reading_time: 7
upvotes: 0
comments: 0
language: en
---

> ## Documentation Index
> Fetch the complete documentation index at: https://daily.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# The Joy of a Single-Purpose Class: From String Mutation to Message Composition

**[arkency](https://daily.dev/sources/arkency)** · 7 min read · 0 upvotes · 0 comments

## Summary

A practical refactoring journey addressing Ruby 3.4's frozen string literal warnings by replacing mutable string concatenation with an immutable array-based approach, then evolving it into a dedicated single-purpose Message class. The solution eliminates primitive obsession, hides implementation details, supports flexible delimiters, and enables clean composition through Ruby's implicit string conversion protocol.

## Full article

daily.dev links to this article rather than hosting it. Read it at the original source: <https://blog.arkency.com/the-joy-of-a-single-purpose-class-from-string-mutation-to-message-composition/>

## Similar posts on daily.dev

- [Frozen String Literals: Past, Present, Future?](https://daily.dev/posts/frozen-string-literals-past-present-future--teqqoxevu) · RUBYLAND · 0 upvotes · 0 comments
- [Short Ruby Newsletter - edition 155](https://daily.dev/posts/short-ruby-newsletter---edition-155-scfr0sh0j) · RUBYLAND · 0 upvotes · 0 comments
- [Polymorphism with Strategies](https://daily.dev/posts/polymorphism-with-strategies-pzrzruoku) · RUBYLAND · 0 upvotes · 0 comments
- [Ruby Classes](https://daily.dev/posts/ruby-classes-nreohkvmx) · RUBYLAND · 0 upvotes · 0 comments

---

Tags: [#general-programming](https://daily.dev/tags/general-programming), [#rails](https://daily.dev/tags/rails), [#ruby](https://daily.dev/tags/ruby)

[View this post on daily.dev](https://daily.dev/posts/the-joy-of-a-single-purpose-class-from-string-mutation-to-message-composition-3rt6wk2qm)