타입으로 견고하게 다형성으로 유연하게 5장 진태영

[jintaeyeong]

타입으로 견고하게 다형성으로 유연하게 첫날 읽을 때는 정적, 동적 언어에 대한 개념부터 시작해서 3,4,5장 페이지를 넘길 수록 어려웠던 부분이 많았던 것 같습니다.
그래도 타입과 다형성이라는 주제로 이야기도 만들어서 최대한 쉽게 이해할 수 있도록 쓰신 것 같습니다.
오버로딩과 오버라이딩에 대한 차이점만 알고 있었지만 책을 읽고 더 확실히 이해하고 사용할 수 있을 것 같습니다!

[github-actions]

우측에 있는 Projects, Milestone, Development를 확인 후 할당 해주세요~! 🙇

[gemini-code-assist]

Hello @jintaeyeong, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

Summary of Changes

This pull request contains a review of Chapters 4 and 5 from the book '타입으로 견고하게 다형성으로 유연하게' (Robust with Type, Flexible with Polymorphism) by jintaeyeong. The review includes keyword summaries, personal reflections, and discussion points related to the content of each chapter. Chapter 4 focuses on generics, type parameter constraints, and variance (covariance, invariance, and contravariance). Chapter 5 covers overloading, overriding, type classes, and kinds. The author shares their understanding of the concepts, difficulties encountered, and questions for discussion.

Highlights

• Chapter 4 Review: Summarizes key concepts from Chapter 4, including generic classes, type parameter constraints (upper bounds, recursive constraints), and variance (covariance, invariance, contravariance).
• Chapter 5 Review: Summarizes key concepts from Chapter 5, including overloading (function, method, operator), overriding, type classes, and kinds. It also includes a comparison table between overloading and overriding.
• Personal Reflections: The author shares their understanding of generics and type parameter constraints, as well as difficulties in understanding contravariance. They also reflect on the new concepts learned and the broader understanding of polymorphism gained from reading the book.
• Discussion Points: The author raises questions for discussion, such as the practical application of variance annotations (out, in) and the preference between overloading and 'or' types in development.

Changelog

• 2025/RobustWithTypeFlexibleWithPolymorphism/jintaeyeong/4장 두 다형성의 만남.md
  • Added a review and keyword summary for Chapter 4.
  • Included sections for 느낀점 (personal reflections) and 논의 내용 (discussion points).
• 2025/RobustWithTypeFlexibleWithPolymorphism/jintaeyeong/5장 오버로딩에 의한 다형성.md
  • Added a review and keyword summary for Chapter 5.
  • Included sections for 느낀점 (personal reflections) and 논의 내용 (discussion points).
  • Added a comparison table for 오버로딩 (overloading) and 메서드 오버라이딩 (method overriding).

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Trivia time!

What is the origin of the term 'polymorphism' in computer science?

Click here for the answer

The term 'polymorphism' comes from the Greek words 'poly' (meaning 'many') and 'morph' (meaning 'form'). It was likely adopted to describe the ability of a single interface to represent many forms of data.

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[gemini-code-assist]

Code Review

The pull request summarizes key concepts from chapters 4 and 5 of the book, focusing on generics, variance, overloading, and overriding. It also includes personal reflections and discussion points. The summaries are well-organized and provide a good overview of the material.

Merge Readiness

The pull request provides a good summary of the chapters and includes thoughtful reflections and discussion points. I am unable to directly approve the pull request, and recommend that others review and approve this code before merging. There are no critical or high severity issues, so the pull request is ready to be merged after addressing the medium severity comments.

[TaeHyoungKwon]

상황에 따라 다르지만, 저는 많은 경우에 일단 이거나 타입으로 일단 작성했었습니다

이후에 오버로딩으로 리팩토링 했었던 걸로 기억이 나네요