Python Exception Handling Error Message
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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 perhaps the most common kind of complaint python get exception message you get while you are still learning Python: >>> while True print('Hello world') File "
Python Exception Class
line 1 while True print('Hello world') ^ SyntaxError: invalid syntax The parser repeats the offending line and displays a little ‘arrow' pointing python exception stack trace at the earliest point 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
Syntax For Generic Except Clause In Python
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 attempt is made to execute it. Errors detected during execution are called exceptions and are not unconditionally fatal: you will soon learn how to python print exception 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 "
Pages Local Site Map ------------------------ Rename Page Delete Page ------------------------ ------------------------ Remove Spam Revert to this revision ------------------------ SlideShow User Login Handling Exceptions The simplest way to handle exceptions is with a "try-except" block: 1
Python Custom Exception
(x,y) = (5,0) 2 try: 3 z = x/y 4 except
Python Try Without Except
ZeroDivisionError: 5 print "divide by zero" If you wanted to examine the exception from code, you python try except else could have: 1 (x,y) = (5,0) 2 try: 3 z = x/y 4 except ZeroDivisionError as e: 5 z = e # representation: " Error: %s
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this http://stackoverflow.com/questions/4308182/getting-the-exception-value-in-python 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 https://www.tutorialspoint.com/python/python_exceptions.htm Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Getting the python exception exception value in Python up vote 90 down vote favorite 9 If I have that code: try: some_method() except Exception,e: How can I get this Exception value (string representation I mean)? Thanks python exception share|improve this question asked Nov 29 '10 at 21:16 Luiz Fernando 1,95751732 add a comment| 4 Answers 4 active oldest votes up vote 113 down vote accepted use str try: some_method() python exception handling except Exception as e: s = str(e) Also, most exception classes will have an args attribute. Often, args[0] will be an error message. It should be noted that just using str will return an empty string if there's no error message whereas using repr as pyfunc recommends will at least display the class of the exception. My take is that if you're printing it out, it's for an end user that doesn't care what the class is and just wants an error message. It really depends on the class of exception that you are dealing with and how it is instantiated. Did you have something in particular in mind? share|improve this answer edited Nov 29 '10 at 21:23 answered Nov 29 '10 at 21:18 aaronasterling 35.8k1084102 I'm printing this to make a report, the str(e) is fine i guess. Thanks a lot –Luiz Fernando Nov 29 '10 at 21:40 3 I would prefer to use e.message because args[0] might not be actually a message. –cedbeu Oct 15 '13 at 10:17 1 repr(e) is also helpful if you want to get the full exception( e.g. NameError("global name 'va
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