How Do I Start When Trying to Find Programming Errors

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JavaScript in Plain English

7 min readMay 6, 2024

How Do I Start When Trying to Find Programming Errors

Let’s face it: errors are a reality of the programming process. Whether you’re an experienced developer or just getting started, facing errors and errors is important.

Fear not, developers! This guide will offer you the knowledge that you need to face these challenges front on and succeed.

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Why Bug Detection is Important

Imagine spending hours creating a stunning website only to have it show a so-called “404 Not Found” error.

Errors not only frustrate users, but they also affect the functioning and speed of your website.

Mastering detection and handling is essential to creating robust and user-friendly apps for the web.

The Many Faces of Errors

Not all errors are created equally. Let’s break down the most common types you’ll face:

Syntax Errors: These are grammatical errors in your code, such as missing a semicolon or using a wrong term. They prevent your code from even running.
Runtime Errors: These errors come up during program execution, mostly as a result of unexpected inputs or scenarios. Dividing by zero is a common runtime error.
Logic Errors: This is when things become tough. Your code might run correctly, however, it delivers wrong results because of errors in the logic you used. Following a recipe with the wrong ingredients leads to a cake that does not meet expectations.
Web Dev-Specific Errors: The web adds its own set of challenges. You might encounter HTTP status code failures (such as 404s or 500s), JavaScript errors in the console, or errors different from frameworks such as React.

Your Debugging Toolbox

Now that you know your opponent, let’s look at the weapons in your debugging collection:

Browser Developer Tools

This built-in detective (similar to Chrome DevTools or Firebug) lets you inspect elements, debug JavaScript, and analyze network queries.

It is an essential tool for web development.

Spending time to learn these tools will pay off during your coding journey.

Debugging Tools

Debuggers, such as the one in VS Code, allow you to go through the code line by line, review variables and set up breakpoints to find the particular point of an error.

These are excellent for challenging problems in which usual solutions come out lacking.

Browser Extensions

Improve your debugging experience by using plugins that highlight syntax problems, check for accessibility queries, and more.

There are a few extensions available that meet specific needs and preferences.

Strategies for Effective Error Handling

Take in the Debugging Mindset: Handle errors with a relaxed and thoughtful mindset. Break the problem down into smaller parts and compare what is expected to what is happening. Don’t be disappointed, careful debugging will lead you to the solution.
The Power of console.log(): This is your secret weapon to track variable values and the development process. Use carefully chosen console.log() lines throughout your code to gain insight into how the app is working.
Break It Down with Breakpoints: Set breakpoints in your code to pause execution at specific lines. This allows you to examine variables and understand the program’s state at that point. Breakpoints are like taking a snapshot of your code’s inner workings, helping you identify where things go wrong.

Avoiding errors before they come up.

Write Clean, Readable Code: Debugging is much simpler when the code is clear and well-commented. Use clear variable names, proper spaces, and comments to show what you are saying. Spending time creating clean code from the start will save you time and frustration in the long run.
The Power of Collaboration: Code reviews and pair programming are great ways to detect errors early on. Get a new set of eyes on your code and learn from one another’s ways. Collaboration is a great way to find errors while supporting better coding practices.
Version Control is Your Savior: Tools like Git help you to track changes, return to previous versions, as well as interact smoothly. This is a savior when debugging gets messy. Git lets you easily return a step if you wrongly create an error.

Modern Debugging Techniques

Using Browser DevTools

Learn to use DevTools to review components, debug JavaScript, and analyze network requests.

This skill will become second nature to every web developer.

Explore and play with DevTools’ big functionality — you may be surprised by what you find!

Understanding Error Messages and Stack Signs

Learn how to read error messages and understand stack patterns.

These signs put you on the proper path to find the main reason for the error.

Error messages can seem hidden at first, but with experience, you will learn how to decode them.

Debugging with Console Logs

I mentioned console.log() as a debugging weapon. Now, let's see how to use it effectively. Place console.log() statements throughout your code to track variable values at different points. This helps you understand how data flows through your program and identify where things might be going astray.

Try-Catch Blocks

For graceful error handling, use try-catch blocks.

These allow you to anticipate potential errors and define how your code should react.

This prevents your program from crashing unexpectedly and provides a more user-friendly experience.

Error Monitoring and Logging

In production scenarios, think about using error monitoring and logging tools.

These tools track errors in real-time, allowing you to effectively find and fix errors before they impact users.

Automated Testing Strategies

Take advantage of automated testing.

Unit and integration tests help to detect errors early on in the development process.

You can avoid errors in your codebase by creating tests that mimic user interactions and expected results.

Practical Error Example

Learning from experience is key. Let’s go through common web development errors and how they’re dealt with:

Scenario:

Imagine someone enters your website and tries to reach a particular page, like “contact-us.html”.

However, instead of the expected content, users receive the dreaded “404 Not Found” warning.

This means that the server had no way to locate the requested object (“contact-us.html” in this example).

Debugging Steps

Now it’s your chance to play detectives! Here is how to detect and fix the 404 error:

Use Browser DevTools: Your browser’s built-in DevTools are a secret tool. Open them (often by pressing F12 or right-clicking and selecting “Inspect”).
Go to the Network Tab: In DevTools, go to the “Network” tab. This shows all of the queries carried out by your browser while loading the page.
Inspect Network Requests: Look for the request corresponding to the issue page (most likely “contact-us.html”). You might see a red status code next to it, which shows an error.
Analyze the Error Status: To get your data, just click on the request. The status code will give useful data. A 404 will most likely return the status code “404 Not Found”. Additionally, the response body might give signs about the missing object.
Verify the File Path: This is the main point of the scenario. Check the file path for the missing object (in this example, “contact-us.html”). Is the file in the right directory on the server? Did you accidentally misspell the filename?

Fixing the 404 Error:

Once you’ve found the reason for the error, it’s time to fix it:

Upload the Missing object: If the file is missing, upload the right “contact-us.html” file to the server’s specified directory.
Correct the File Path: If your code has a wrong file path (HTML links, JavaScript references), change the path to point to the correct object location.
Clear Your Browser Cache: Outdated cached data might trigger 404 errors. Clear your browser’s cache and try browsing the website again.

This was the most common error example. Each bug is unique, but the strategies suggested in this guide will help you deal with them successfully.

Pro Tips and Best Practices

Write Clean Code: Try writing clean, well-commented code from the very beginning. This not only reduces debugging for you but also boosts code maintainability for future projects or collaboration.
Test-Driven Development (TDD): Think about exploring Test-Driven Development (TDD). The technique involves creating unit tests before creating actual code. It requires you to think about both the desired behavior and potential edge situations, leading to more robust and error-resistant code.
Version Control Systems (VCS): Always use a version control system (VCS), such as Git. It helps you to track changes, return to previous versions if necessary, and work smoothly with other developers.