What is a co-smell and how to identify it?
The term co-smell is fundamental to ensure that the code we develop is efficient and understandable. It is a concept that refers to the "feeling" that something is not right in the code, similar to when something "smells bad". Although we do not have an exact equivalent in English, we can say that we perceive that something is not right or can be improved. These perceptions develop with practice and experience, allowing us to identify errors quickly. Let's explore some common examples of co-smells and how to recognize them.
How do we recognize a co-smell in the appointment?
One of the most common co-smells is the improper naming of variables, methods or classes. Names should be as descriptive as possible. Otherwise, when reading the code, the lack of clarity in the names can confuse the developer and make it difficult to understand the logical flow. If the names do not correctly inform about their function or content, there is a high probability that we are dealing with a co-smell.
Are long methods and classes an indicator?
Yes, overly long classes and methods represent another co-smell. Although there is no exact standard for length, if a class exceeds 1000 or 1500 lines of code, it is a red flag. Generally, this indicates that the class has too many responsibilities that could be divided into smaller, specialized components, thus improving code comprehension and maintainability.
What happens with methods that use many parameters?
When a method or function begins to accumulate many parameters, it can trigger a co-smell. The multiplicity of parameters can indicate that there is a lot of logic and flows within the function that complicate its readability. If you see a method overloaded with parameters, it is likely that internally there are problems that need to be evaluated and corrected.
What are magic numbers and how to avoid them?
"Magic numbers" are numeric values that are directly inserted into the code, without a clear explanation of their purpose. Their use is considered bad practice because developers must perform additional analysis to understand what they mean and why they are there. This co-smell can be solved by using constants with descriptive names or by enumerations.
enum Menu{ Add = 1, Remove = 2, List = 3, Exit = 4}
In this example, we have replaced straightforward numbers with a clear enumeration for a menu, which makes the code easier to understand. Thus, instead of the number, we see a name that explains the functionality.
How to improve the code by avoiding co-smells?
The key to avoid co-smells is to apply good practices from the beginning of the development:
- Descriptive name: Use clear and meaningful names for variables, functions and classes.
- Divide and conquer: If a method or class is too large, break it into smaller, more manageable parts.
- Avoid excessive parameters: If a method needs too many parameters, review its structure; it may need to be reorganized or subdivided.
- Assign meanings: Replace magic numbers with constants or descriptive enumerations.
These tips are not exhaustive, but they are a good starting point. Exploring documentation and continuing to learn about new coding practices will be crucial to refine your skills. The world of development is vast and there is always something new to learn!
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