Pyhton Error
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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 Custom Exception
perhaps the most common kind of complaint you get while you are still python exception message learning Python: >>> while True print('Hello world') File "
Syntax For Generic Except Clause In Python
token preceding the arrow: in the example, the error is detected at the function 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
Python Raise Valueerror
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 "
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 (x,y) = (5,0) 2 try: 3 z = x/y 4 except ZeroDivisionError: 5 print "divide by zero" If you wanted python print exception to examine the exception from code, you could have: 1 (x,y) = (5,0) 2
Python Try Without Except
try: 3 z = x/y 4 except ZeroDivisionError as e: 5 z = e # representation: " Error: %s
This module makes available standard errno system symbols. The value of each symbol is the corresponding integer https://docs.python.org/2/library/errno.html value. The names and descriptions are borrowed from linux/include/errno.h, http://stackoverflow.com/questions/1483429/how-to-print-an-error-in-python which should be pretty all-inclusive. errno.errorcode¶ Dictionary providing a mapping from the errno value to the string name in the underlying system. For instance, errno.errorcode[errno.EPERM] maps to 'EPERM'. To translate a numeric error code to an error python exception message, use os.strerror(). Of the following list, symbols that are not used on the current platform are not defined by the module. The specific list of defined symbols is available as errno.errorcode.keys(). Symbols available can include: errno.EPERM¶ Operation not permitted errno.ENOENT¶ No such file or directory errno.ESRCH¶ No python custom exception such process errno.EINTR¶ Interrupted system call errno.EIO¶ I/O error errno.ENXIO¶ No such device or address errno.E2BIG¶ Arg list too long errno.ENOEXEC¶ Exec format error errno.EBADF¶ Bad file number errno.ECHILD¶ No child processes errno.EAGAIN¶ Try again errno.ENOMEM¶ Out of memory errno.EACCES¶ Permission denied errno.EFAULT¶ Bad address errno.ENOTBLK¶ Block device required errno.EBUSY¶ Device or resource busy errno.EEXIST¶ File exists errno.EXDEV¶ Cross-device link errno.ENODEV¶ No such device errno.ENOTDIR¶ Not a directory errno.EISDIR¶ Is a directory errno.EINVAL¶ Invalid argument errno.ENFILE¶ File table overflow errno.EMFILE¶ Too many open files errno.ENOTTY¶ Not a typewriter errno.ETXTBSY¶ Text file busy errno.EFBIG¶ File too large errno.ENOSPC¶ No space left on device errno.ESPIPE¶ Illegal seek errno.EROFS¶ Read-only file system errno.EMLINK¶ Too many links errno.EPIPE¶ Broken pipe errno.EDOM¶ Math argument out of domain of func errno.ERANGE¶ Math result not representable errno.EDEADLK¶ Resource deadlock would occur errno.ENAMETOOLONG¶ File name too long errno.ENOLCK¶ No record locks available errno.ENOSYS¶ Func
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 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 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up How to print an error in Python? up vote 118 down vote favorite 32 try: something here except: print 'the whatever error occurred.' How can I print the error in my except: block? python error-handling exception-handling share|improve this question edited Jan 1 at 6:49 Slothworks 470514 asked Sep 27 '09 at 11:48 TIMEX 41.2k201525826 6 The currently accepted answer doesn't work in Python 3, and the prettier except Exception as e: syntax has existed since Python 2.6 (which, incidentally, had been out for a year before even the accepted answer was posted 6 years ago). Pretty much nobody is using 9-year-old Python 2.5 or earlier nowadays, and Python 3's popularity is growing relative to 2.7. It would be helpful for future visitors if you were to accept ilya n's answer instead, since it covers all Python versions; could you please do so? –Mark Amery Nov 4 '15 at 11:50 add a comment| 5 Answers 5 active oldest votes up vote 191 down vote accepted except Exception,e: print str(e) share|improve this answer answered Sep 27 '09 at 12:19 jldupont 41.9k32140259 11 the str() part is redundant -- print e is exactly the same thing as print str(e) [[i.e., print does its own stringification]]. –Alex Martelli Sep 27 '09 at 16:40 4 @alex: doesn't it depends on the subclass (if any) of the exception thrown? The repr method might not have been implemented whilst the str might have. In any case, there isn't a good substitute for an incomplete implementation I guess ;-) –jldupont Sep 27 '09 at 17:04 24 fwiw in python3 need to use except Exception as e like the other answers –Sam Watkins Jul 1 '14 at 6:02 2 str( KeyError('bad')) => 'bad' -- doesn't tell exception type –Dave Aug 28 '15 at 16: