Python Catching Multiple Error Types
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you have probably seen some. There are (at least) two distinguishable kinds of errors: syntax errors and exceptions. 8.1. Syntax handling multiple exceptions python Errors¶ Syntax errors, also known as parsing errors, are perhaps the most
Python Raise Multiple Exceptions
common kind of complaint you get while you are still learning Python: >>> while True print 'Hello python exception class world' File "
Python Try Except Multiple Times
look in case the input came from a script. 8.2. Exceptions¶ Even if a statement or expression is syntactically correct, it may cause an error when an attempt is made to execute it. Errors detected during execution are called exceptions and are not unconditionally fatal: you will soon learn how to handle them in Python programs. Most exceptions are not handled by programs, however, and result in error messages as shown here: >>> 10 * (1/0) Traceback (most recent call last): File " you have probably seen some. There are (at least) two distinguishable kinds of errors: syntax errors and exceptions. 8.1. Syntax Errors¶ Syntax errors, also known as parsing errors, are perhaps the most common kind of complaint you get python exception stack trace while you are still learning Python: >>> while True print('Hello world') File " in the line where the error was detected. The error is caused by (or at least detected at) the token preceding the arrow: in the example, the error is detected at the function print(), since a colon https://docs.python.org/2.7/tutorial/errors.html (':') is missing before it. File name and line number are printed so you know where to look in case the input came from a script. 8.2. Exceptions¶ Even if a statement or expression is syntactically correct, it may cause an error when an attempt is made to execute it. Errors detected during execution are called exceptions and are not unconditionally fatal: you will soon learn how to handle them in Python programs. Most exceptions https://docs.python.org/3/tutorial/errors.html are not handled by programs, however, and result in error messages as shown here: >>> 10 * (1/0) Traceback (most recent call last): File " Leave a comment Hi all, Today i want to give you a very small tip about handling multiple exceptions within one except statement. Let's suppose that you https://artemrudenko.wordpress.com/2013/09/16/python-multiple-exceptions-in-one-except-block/ have the following code: try: Do smth except ValueError: print "error" except AttributeError: print "error" Now you want to raise the same action in both cases for ValueError and http://www.jython.org/jythonbook/en/1.0/ExceptionHandlingDebug.html AttributeError. In python documentation(http://docs.python.org/2/tutorial/errors.html#handling-exceptions) you can find that: An except clause may name multiple exceptions as a parenthesized tuple. This means that you can update your code the following python exception way: try: Do smth except (ValueError, AttributeError): print "error" Note that the parentheses around this tuple are required, because except ValueError, e: was the syntax used for what is normally written as except ValueError as e: in modern Python. The old syntax is still supported for backwards compatibility. This means except RuntimeError, TypeError is not equivalent to python catching multiple except (RuntimeError, TypeError): but to except RuntimeError as TypeError: which is not what you want. That's all, hope this post will be helpful Best regards, Artem Share this:TwitterFacebookLike this:Like Loading... Related Leave a Reply Cancel reply Enter your comment here... Fill in your details below or click an icon to log in: Email (required) (Address never made public) Name (required) Website You are commenting using your WordPress.com account. (LogOut/Change) You are commenting using your Twitter account. (LogOut/Change) You are commenting using your Facebook account. (LogOut/Change) You are commenting using your Google+ account. (LogOut/Change) Cancel Connecting to %s Notify me of new comments via email. Python: Getting unique values from list. Introduction tosets. Python speed up Pages About Category Python (28) Decorators (3) Dictionary (4) Excel (2) List Comprehension (3) Lists (11) Samples (16) Sets (1) XML (1) Tips (3) Uncategorized (1) Usefull Links (4) Archives August 2014 July 2014 March 2014 February 2014 November 2013 September 2013 April 2013 Create a free website or blog at WordPress.com. %d bloggers like this: end-user then by having them run into an issue with your software and displaying a big ugly error message on the screen, followed by a program crash. Exception handling is all about ensuring that when your program encounters an issue, it will continue to run and provide informative feedback to the end-user or program administrator. Any Java programmer becomes familiar with exception handling on day one, as some Java code won’t even compile unless there is some form of exception handling put into place via the try-catch-finally syntax. Python has similar constructs to that of Java, and we’ll discuss them in this chapter. After you have found an exception, or preferably before your software is distributed, you should go through the code and debug it in order to find and repair the erroneous code. There are many different ways to debug and repair code; we will go through some debugging methodologies in this chapter. In Python as well as Java, the assert keyword can help out tremendously in this area. We’ll cover assert in depth here and learn the different ways that it can be used to help you out and save time debugging those hard-to-find errors. Exception Handling Syntax and Differences with Java¶ Java developers are very familiar with the try-catch-finally block as this is the main mechanism that is used to perform exception handling. Python exception handling differs a bit from Java, but the syntax is fairly similar. However, Java differs a bit in the way that an exception is thrown in code. Now, realize that I just used the term throw…this is Java terminology. Python does not throw exceptions, but instead it raises them. Two different terms which mean basically the same thing. In this section, we’ll step through the process of handling and raising exceptions in Python code, and show you how it differs from that in Java. For those who are unfamiliar, I will show you how to perform some exception handling in the Java language. This will give you an opportunity to compare the two syntaxes and appreciate the flexibility that Python offers. Listing 7-1. Python Print Exception