In this tutorial, you will learn about different types of errors and exceptions that are built-in to Python. They are raised whenever the Python interpreter encounters errors. Show Video: Python Exception Handling
We can make certain mistakes while writing a program that lead to errors when we try to run it. A python program terminates as soon as it encounters an unhandled error. These errors can be broadly classified into two classes:
Python Syntax ErrorsError caused by not following the proper structure (syntax) of the language is called syntax error or parsing error. Let's look at one example: >>> if a < 3 File "<interactive input>", line 1 if a < 3 ^ SyntaxError: invalid syntaxAs shown in the example, an arrow indicates where the parser ran into the syntax error. We can notice here that a colon : is missing in the if statement. Python Logical Errors (Exceptions)Errors that occur at runtime (after passing the syntax test) are called exceptions or logical errors. For instance, they occur when we try to open a file(for reading) that does not exist (FileNotFoundError), try to divide a number by zero (ZeroDivisionError), or try to import a module that does not exist (ImportError). Whenever these types of runtime errors occur, Python creates an exception object. If not handled properly, it prints a traceback to that error along with some details about why that error occurred. Let's look at how Python treats these errors: >>> 1 / 0 Traceback (most recent call last): File "<string>", line 301, in runcode File "<interactive input>", line 1, in <module> ZeroDivisionError: division by zero >>> open("imaginary.txt") Traceback (most recent call last): File "<string>", line 301, in runcode File "<interactive input>", line 1, in <module> FileNotFoundError: [Errno 2] No such file or directory: 'imaginary.txt'Python Built-in ExceptionsIllegal operations can raise exceptions. There are plenty of built-in exceptions in Python that are raised when corresponding errors occur. We can view all the built-in exceptions using the built-in local() function as follows: print(dir(locals()['__builtins__']))locals()['__builtins__'] will return a module of built-in exceptions, functions, and attributes. dir allows us to list these attributes as strings. Some of the common built-in exceptions in Python programming along with the error that cause them are listed below:
If required, we can also define our own exceptions in Python. To learn more about them, visit Python User-defined Exceptions. We can handle these built-in and user-defined exceptions in Python using try, except and finally statements. To learn more about them, visit Python try, except and finally statements. What are the 3 types of exceptions?There are three types of exception—the checked exception, the error and the runtime exception.
What are exceptions in C?C # in Telugu
An exception is a problem that arises during the execution of a program. A C++ exception is a response to an exceptional circumstance that arises while a program is running, such as an attempt to divide by zero.
What is exception handling in c3?Exceptions provide a way to transfer control from one part of a program to another. C# exception handling is built upon four keywords: try, catch, finally, and throw. try − A try block identifies a block of code for which particular exceptions is activated. It is followed by one or more catch blocks.
What are the 3 blocks used to handle exception?The "finally" block is used to execute the necessary code of the program. It is executed whether an exception is handled or not. The "throw" keyword is used to throw an exception. The "throws" keyword is used to declare exceptions.
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