When it comes to code metrics like class size, function parameters, and related guidelines, best practices can vary based on the context of the project, language, and team standards. However, here are some general recommendations:
- Lines of Code (LOC): Aim to keep classes between 200-400 lines of code. If a class exceeds this, consider breaking it down into smaller, more focused classes. Large classes can become difficult to manage, test, and understand.
- Single Responsibility Principle (SRP): Each class should have a single responsibility or purpose. If a class is doing too much, it might be a sign to refactor it into multiple classes.
- Lines of Code (LOC): A function should ideally be between 10-30 lines of code. If a function exceeds 50 lines, it's likely doing too much and could be broken down into smaller, more focused functions.
- Cohesion: Ensure each function performs a single task or operation. This improves readability, reusability, and testability.
- Optimal Number: Functions should generally have no more than 3-4 parameters. If more parameters are needed, consider refactoring by using objects or data structures to encapsulate related parameters.
- Named Arguments (in languages that support them): Using named arguments can improve readability, especially when dealing with multiple parameters or parameters of the same type.
- Ideal Range: Aim for a cyclomatic complexity of 5 or less per function. Higher complexity can indicate that a function has too many conditional paths and might need refactoring.
- Impact: Lower complexity typically results in code that is easier to test and maintain.
- Depth of Inheritance Tree (DIT): Aim to keep the inheritance tree shallow, generally no deeper than 3-5 levels. Deep inheritance trees can make the codebase difficult to understand and maintain.
- Composition Over Inheritance: Favor composition over inheritance where possible, as it often leads to more flexible and maintainable designs.
- Coupling: Strive for low coupling between classes and modules. High coupling makes the system harder to change and more prone to bugs.
- Cohesion: Ensure high cohesion within a class, meaning that its methods and variables are closely related to each other.
- Inline Comments: Use comments sparingly and only when necessary to clarify complex logic. Over-commenting can clutter the code and make it harder to read.
- Self-Documenting Code: Favor clear and descriptive variable and method names that make the code self-explanatory without needing many comments.
- Optimal Range: Classes should typically have 10-20 methods. If a class has significantly more, consider splitting the class to adhere to the Single Responsibility Principle (SRP).
These guidelines help in maintaining a clean, manageable, and scalable codebase. However, they should be adapted to fit the specific needs of your project and team.
