What are Errors and Exceptions in Python - Explained in Deep

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Mistakes in computer programs can make things go wrong or even make the program stop working. Luckily, Python, the friendly programming language, has some tools to fix these problems and make the code stronger. This guide will help us understand different types of errors and exceptions in Python and how to deal with them.

Meaning of Errors and Exceptions in Python

The error message indicates a shortage of system resources. On the other hand, exceptions can occur at runtime or compile time. The following section will elaborate on the differences between them. As a result, it will be beneficial to you to know the concepts in-depth.

What is the Difference Between Exception and Error?

Errors can pop up when you're driving. These can be anything from getting lost because you misread the syntax error, taking the wrong logical error, or finding a library incompatibility. These errors can happen, and they're often not something we can control.

Now, exceptions are like having a backup plan when those errors appear. Exceptions are a way for programmers to create those detours in their code. If something unexpected comes up, like not finding a file or getting unexpected data, the program doesn't just crash. It catches that exception, deals with it, and keeps going.

So, in simple terms, errors are the surprises that might happen, and they're often out of our hands. On the other hand, exceptions contain a Plan B for your code. Moreover, it makes it more flexible and able to handle the unexpected twists that might come its way.

Types of Errors and Exceptions in Python

Now, we’ll discuss key errors in Python.
 

1. Syntax Error: Syntax errors happen when you don't write your instructions in a way the computer understands, like using the wrong words or forgetting important punctuation.
2. Type Error: This error shows when you try to do something similar.
3. Name Error: If you ask the computer to use a name it doesn't recognize, it gets confused. This error tells you that the name you used isn't known.
4. Index Error:  If you're working with a list of things and ask for something that needs to be added, the computer gets lost. This error warns you about going too far or not far enough.
5. Key Error: This error is like the computer telling you the page you want isn't in the book.
6. Value Error: Giving the computer something it can't use or understand raises this error. For example, it can ask it to turn words into numbers when it's not possible.
7. Attribute Error: If you press a button that isn't there, the system can confused. 
8. IO Error: If the computer reads or writes something and something goes wrong, it raises this error.
9. ZeroDivision Error: If you try to split a number into zero parts, the computer doesn't know what to do. As a result, it gives you this error.
10. ImportError: When you ask the computer to bring in a unique tool and can't find it, this error pops up.
11. Logical Errors: In Python, it happens when your code is like a well-behaved robot following instructions, but those instructions have a mistake when they're set up. You need to figure out where you made the mistake in your thinking or the steps you told the computer to take.

Here, we’ve discussed all types of errors and exceptions in Python.

Syntax of Error and Exception

As you saw above, we’ve gone through all Python errors and exceptions. Now, The following section will elaborate on the syntaxes of error and exception. First, we will discuss the error and then the exception. 

Syntax of Error

myfunction(x, y):

return x + y

else:

print("Hello!")

if mark >= 50

print("You passed!")

if arriving:

print("Hi!")

esle:

print("Bye!")

if flag:

print("Flag is set!")

Syntax of Exception

# initialize the amount variable

marks = 10000

# perform division with 0

a = marks / 0

print(a)

Here, you’ve seen all types of errors in Python and the syntax of error and exception.

Exception Handling in Python

Until now, the computer programs we've created didn't pay much attention to the idea that things might go wrong. Sure, we tried our best to avoid mistakes when using data, but if something unexpected happened, our programs just crashed suddenly.

In computer programs, some situations are where things might not go as planned, like when trying to read a file or getting information from a user. Good programmers think ahead and add safety nets to their programs, so if something predictable goes wrong, the program doesn't just give up. If we know a specific part of our program might cause trouble, we can tell the computer what to do if that happens. Instead of letting the problem crash our program, we can catch it, fix things up, and keep going.

In the world of coding, we call the issues that can pop up 'exceptions.' These exceptions have occurred, and our program needs help to keep going. All these exceptions are like special categories, and we can learn how to deal with them so that our programs can handle unexpected twists and turns.

After learning all the kinds of errors and exceptions in Python, we will proceed further towards handling exceptions.

How to Handle Exceptions?

When something unexpected happens in our program, it's a hiccup that messes up the usual flow. In the coding world, when a problem, or 'exception,' comes up, Python tries to fix it. Python is investigating where the issue happened. It looks to see if the problem line is inside a 'try block.' If it is, Python checks there's a unique plan, an 'except block,' to handle that type of problem. The program follows that plan, fixes things, and keeps going from where it left off.

Now, if there's no plan or the problem line isn't inside a 'try block,' Python doesn't give up. It goes up a level. If the issue is inside a function, that function stops, and the line that calls the function can cause the problem. This detective work continues until a plan is found or until we're back to the primary part of the program. But don't worry, it leaves a trail behind, so we can see where the problem started.

Concluding Words

Unit testing and exception handling come in for Python programming and making sure your code is top-notch and ready for action. In this guide, we explored the errors and exceptions in Python, figuring out how to deal with them like a pro. We even know different types of both of them. In short, we learned about all errors in Python. Plus, we went a step further by handling exceptions. It's all about making your code strong, resilient, and ready to handle anything that comes its way in the real world of programming.

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