Immutable State Update

Modern JavaScriptmedium

Course · Section 17: Modern JavaScript Development: Modules, Tooling, and Functional · Lecture 294: Declarative and Functional JavaScript Principles

Implement `updateScore(state, points)` returning a new state object with `score` increased by `points`, without mutating the original.

Input: updateScore({"score":10}, 5)

Output: {"score":15}

Input: updateScore({"score":0,"level":1}, 3)

Output: {"score":3,"level":1}

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Common pitfalls

Approach & explanation (try first)

Spreading into a new object with an updated score keeps the update immutable.

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