Code That's Easy to Read (and Write!)

Ever stared at a bunch of code and thought, "What in the world is this?" Or spent hours trying to fix something simple, only to find a mess of tangled connections? We've all been there. Good code isn't just fancy talk; it's what makes software easy to work with, both now and later. We know the SOLID principles are a good start, but let's look at some other ways to make our code better. I apply these principles in my job everyday.

Section 1: SOLID: Building a Strong Foundation

SOLID principles, when applied thoughtfully, can transform a chaotic codebase into a robust and adaptable system.

S- Single Responsibility Principle (SRP)
Each class or function should have one job and do it well. When a class handles multiple responsibilities, it becomes harder to test and modify. For example, imagine a ReportGenerator class that handles both data retrieval and PDF generation. This violates SRP because it combines two distinct concerns. A better approach would be to separate data retrieval into a DataService and PDF generation into a PdfGenerator. This separation makes each component easier to manage and reuse.

O- Open/Closed Principle (OCP)

Software entities should be open for extension but closed for modification. This means that adding new functionality shouldn't require modifying existing code. For instance, if you need to add a new report format, modifying the ReportGenerator class directly violates OCP. Instead, you can use interfaces or abstract classes to allow extensions without changing the existing structure. This ensures that the original code remains stable while still allowing new features.

L- Liskov Substitution Principle (LSP)
This is a principle I struggled to understand. To follow LSP, ensure that subclasses maintain the fundamental behavior of their base classes.
An example is when a Square class inherits from a Rectangle class but modifying the width unexpectedly changes the height. This breaks the expected behavior, violating LSP.

I- Interface Segregation Principle (ISP)
Clients should not be forced to depend on interfaces they do not use. Instead of creating a large interface with many unrelated methods, it's better to break it down into smaller, more specific interfaces. For example, a Worker interface with methods like eat(), work(), and sleep() forces a Robot class to implement unnecessary eat() and sleep() methods. A better approach is to create separate interfaces like Workable and Consumable, ensuring that each class only implements relevant methods.

D - Dependency Inversion Principle (DIP)

High-level modules should not depend on low-level modules. Instead, both should depend on abstractions. If a ReportService directly depends on a Database class, it creates tight coupling, making the system less flexible. A better solution is to depend on an abstraction like IDataProvider, which allows the database implementation to change without affecting the rest of the system.

More Principles Beyond SOLID

While SOLID principles form a strong foundation, additional best practices can further improve code quality.

One key principle is Don't Repeat Yourself (DRY). Repeating code leads to inconsistencies and maintenance headaches. For example, validation logic should be handled by a separate utility function rather than being duplicated across multiple components.

Another useful principle is Keep It Simple, Stupid (KISS). Overly complex code is difficult to understand and maintain. Favor simple solutions over convoluted ones. For example, a simple if/else block is often preferable to deeply nested loops that make the logic harder to follow.

Similarly, You Ain't Gonna Need It (YAGNI) is against adding unnecessary features based on speculation. Writing code for potential future needs can lead to unnecessary complexity and maintenance burdens. Instead, focus on current requirements and add features only when they are truly needed.

The Principle of Least Astonishment (POLA) emphasizes that code should behave in a way that meets user expectations. Naming variables and functions clearly ensures that their purpose is obvious. For instance, a function named calculateTotal() should return a total, not a subtotal, to avoid confusion.

Conclusion:

Writing good code takes time and effort, but it's worth it in the long run. It makes your work easier and helps others understand your code, making collaboration much smoother. Let's all try to write code that's easy to use and maintain.