Python Try Except 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 Errors¶ Syntax errors, also known as parsing errors, are
Python Exception Class
perhaps the most common kind of complaint you get while you are still learning python exception message Python: >>> while True print 'Hello world' File "
Syntax For Generic Except Clause In Python
The parser repeats the offending line and displays a little ‘arrow' pointing at the earliest point in the line where the error was detected. The error is caused by (or at least detected python exception stack trace at) the token preceding the arrow: in the example, the error is detected at the keyword print, since a colon (':') 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 python custom exception 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 "
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Python Print Exception
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Python Catch Multiple Exceptions
minute: Sign up python: How do I know what type of exception occured? up vote 64 down vote favorite 24 I have a function called by the main program: try: someFunction() except: print "exception happened!" but in the middle of the https://docs.python.org/2.7/tutorial/errors.html execution of the function it raises exception, so it jumps to the except part. How can I see exactly what happened in the someFunction() that caused the exception to happen? python exception share|improve this question edited Apr 30 '12 at 13:41 asked Mar 22 '12 at 14:08 Shang Wang 11.6k53164 3 Never ever ever use bare except: (without a bare raise), except maybe once per program, and preferably not then. –Mike Graham Mar 22 '12 at 14:18 If you use http://stackoverflow.com/questions/9823936/python-how-do-i-know-what-type-of-exception-occured multiple except clauses you wont need to check the exception type, that is what is usually done to act accordingly to a specific exception type. –Rik Poggi Mar 22 '12 at 14:29 1 If you care about the type of exception, it's because you've already considered what types of exception might logically occur. –Karl Knechtel Mar 22 '12 at 14:48 add a comment| 10 Answers 10 active oldest votes up vote 122 down vote accepted The other answers all point out that you should not catch generic exceptions, but no one seems to want to tell you why, which is essential to understanding when you can break the "rule". Here is an explanation. Basically, it's so that you don't hide the fact that an error occured the specifics of the error that occured (error hiding antipattern) So as long as you take care to do none of those things, it's OK to catch the generic exception. For instance, you could provide information about the exception to the user another way, like: Present exceptions as dialogs in a GUI Transfer exceptions from a worker thread or process to the controlling thread or process in a multithreading or multiprocessing application So how to catch the generic exception? There are several ways. If you just want the exception object, do it like this: try: someFunction() except Exception as ex: template = "An exception of type {0} occured. Arguments:\n{1!r}" message = template.format(type(ex).__name__, ex.args) print message Make sure m
here for a quick overview of the site Help Center Detailed answers to any questions you http://stackoverflow.com/questions/1278705/python-when-i-catch-an-exception-how-do-i-get-the-type-file-and-line-number might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of python exception 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Python When I catch an exception, how do I get the type, file, and line number? up vote 115 down vote favorite 40 Catching an exception that would print like this: Traceback (most recent call last): python try except File "c:/tmp.py", line 1, in