You join independent information TL;DR: Don't mix ortoghonal behavior Problems Maintainability Error Prone Performance Penalties Premature optimization principle violation The principle of least astonishment Violation Bijection Duplication of Logic on breaking the attributes Coupling Solutions Break Orthogonal behavior and properties Context Parsing data is always a problem, where joining elements is much easier than breaking them. If you use a separator to break the attributes, you need to make sure the separator does not belong to the domain, and you should escape it. If you map your data to relational databases, search queries will be more difficult and less performant for concatenated attributes. Sample Code Wrong class Point {
    constructor(coordString) {
        this.coordString = coordString;
    }

    x() {
        const coords = this.coordString.split(',');
        if (coords.length !== 2) {
            throw new Error('Invalid coordinate string format');
        }
        return parseFloat(coords[0]);
    }

    y() {
        const coords = this.coordString.split(',');
        if (coords.length !== 2) {
            throw new Error('Invalid coordinate string format');
        }
        return parseFloat(coords[1]);
    }
} Right class Point {
    constructor(x, y) {
        this.x = x;
        this.y = y;
    }
} Detection Semi-Automatic [x] This is a semantic smell, but you can find suspicious concatenation actions on peer reviews. Tags Coupling Level Beginner [x] AI Assistants AI Assistants don't usually suggest this kind of premature optimization of bad rules. Conclusion Don't mix unrelated things since breaking things is always harder than having them separated. Relations Code Smell 20 - Premature Optimization Disclaimer Code Smells are my . opinion Credits Photo by on Tomas Sobek Unsplash Design is choosing how you will fail. Ron Fein Software Engineering Great Quotes This article is part of the CodeSmell Series. How to Find the Stinky Parts of your Code

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Code Smell 243 - Concatenated Properties

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