Programming is a technology that pays attention to logic and details. Especially for novice programmers, they often face various mistakes during the learning process. Whether the program cannot be executed due to grammatical errors, or the functions deviate from expectations due to logic errors, if these problems are not paid attention to, they may have a serious impact on the stability and performance of the program.
In this article, we will take an in-depth look at common mistakes in programming and how to optimize efficiency. We will particularly focus on how to improve the correctness and maintainability of programs through debugging and lint tools. This article will introduce effective error handling techniques, including how to use logging to track the source of the problem, and avoid common program pitfalls through code review.
Whether you are a novice in programming or an experienced engineer, this article will provide you with valuable information to help you master the key skills in the program development process, so as to write cleaner, more efficient programs with fewer errors!
Common mistakes made by new programmers
syntax error
What is a syntax error?
Syntax errors refer to code that does not conform to programming language conventions, usually due to incorrect spelling, missing symbols, or incorrect use of symbols. Such errors are usually detected before compilation or execution, and developers are prompted to correct them, but these errors are still one of the most common problems encountered by many beginners.
Common types of syntax errors
1. Forgot the semicolon
In many programming languages (such as Java, C, C++), a semicolon (;) is required at the end of each line of statement to indicate the end of the statement. Forgetting a semicolon often results in syntax parsing errors, preventing the editor or interpreter from correctly understanding the code.
example:
Solution: Remember to check for semicolons at the end of each line, or use an automatic formatting tool (such as Prettier) to automatically correct such details.
2. Spelling errors
Misspelling variable names, function names or reserved words is also one of the common errors. Many programming languages are case-sensitive, so thefunction spelled as Function, or change the variable myVariablewritten as myvariable, will cause the program to fail to run.
example:
Solution: Use an editor with grammar highlihjt function, such as VS Code or PyCharm. These tools will detect spelling errors in real time and give prompts.
3. Mismatched brackets and quotes
Asymmetry or missing parentheses or quotation marks can also cause syntax errors. These errors often cause unexpected execution and are not immediately noticeable.
example:
Solution: Use the editor's built-in autocompletion feature, or use formatting tools to keep brackets and quotes symmetrical.
4. Incorrect indentation
In languages like Python that rely on indentation, incorrect indentation will directly affect the logic of the program and lead to syntax errors. For example, code within a function or conditional block will not execute correctly if it is not indented correctly.
example:
Solution: Use a code editor with indentation guidelines and enable automatic formatting.
Tips to avoid grammatical errors
- Use auto-complete tools: editors such as Visual Studio Code and JetBrains series (such as WebStorm, PyCharm) have themSmart autocomplete feature, which can instantly help you complete the code and reduce grammatical errors.
- Enable real-time error checking: Editors often have built-in real-time error checking that can detect syntax problems as you type.
- Multiple tests and multiple runs: after each part of the code is written,Test now, confirm that it is correct before continuing writing. This can catch grammatical errors early and avoid difficulties in correcting them later.
logic error
What is a logical error?
Logic errors are usually caused by omissions in the developer's thinking. The program code can be executed normally, but the results are not as expected. This kind of bug is usually not detected during the writing phase, but exhibits incorrect behavior at execution time.
How to spot logic errors
1. Unit testing
Unit testing is an automated testing method that can independently test each small unit of the program to ensure that itCan operate correctly under different conditions. By writing test cases that cover various boundary conditions, logic errors can be discovered and corrected early.
example:
2. Debugging
Debug tools can execute the program code step by step and display the current values and status of variables, helping developers understand the running process of the program and locate logic errors.
Common debug tools include:
- VS Code Built-in Debug function
- Chrome DevTools(for JavaScript Debug)
- PyCharm(for Python Debug)
3. Logging
By adding logs to the program, each step of the program and the values of important variables can be recorded during execution to help analyze logic errors.
example:
Tips to avoid logic errors
- Think about flow charts: Draw a flow chart before writing a program. This will help you understand the logical flow more clearly and reduce the chance of errors.
- Keep your program simple: avoid concentrating too much logic into one function or block, insteadSplit the program into small, single-responsibility modules, helping to detect and correct logic errors more easily.
- Conduct more boundary testing: When testing, you should not only consider normal situations, but also test extreme or exceptional situations, which can help find logical loopholes in the program early.
Implementation suggestions
1. Follow naming conventions
Good naming habits can make your code easier to read and maintain. The names of variables and functions should clearly describe their function, rather than using single-letter or irrelevant names.
example:
2. Avoid overly complex code
The readability and maintainability of program code are very important. Overly complex logic can easily lead to errors and will be more difficult to modify in the future. Keep each function with a single responsibility and split your code appropriately.
3. Continuous testing
Even if the program works properly, regular testing is necessary. Especially after functional changes, you should ensure that each part can execute stably. Using automated testing tools, such as JUnit, pytest, etc., can help maintain program code quality.
Error management tools
1. Lint tool
Lint tools can automatically analyze program code, help developers find potential errors, and provide optimization suggestions. Common Lint tools include:
- ESLint: for JavaScript
- Pylint: for Python
- Checkstyle: for Java
2. Version control system
Using a version control system (such as Git) can help developers track the history of code changes and quickly roll back to a previous stable version when problems arise.
3. Bug tracking tool
When the project scale is large, using error tracking tools (such as Sentry, Bugsnag) can help developers instantly capture and analyze running errors, and provide detailed error logs to quickly locate problems.
Conclusion
Programming is a process of continuous learning and error correction. By avoiding common grammatical and logical errors, the stability and quality of the program can be effectively improved. In addition, making good use of error management tools and debugging methods will solve problems faster and improve development efficiency. Continuous practice and learning are key to avoiding mistakes and becoming a better developer!
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