Python: How to Ignore an Exception and Proceed

Python: How to ignore an exception and proceed?

except Exception:
    pass

Python docs for the pass statement

How to properly ignore exceptions

try:
    doSomething()
except Exception: 
    pass

or

try:
    doSomething()
except: 
    pass

The difference is that the second one will also catch KeyboardInterrupt, SystemExit and stuff like that, which are derived directly from BaseException, not Exception.

See documentation for details:

• try statement
• exceptions

However, it is generally bad practice to catch every error - see Why is "except: pass" a bad programming practice?

Ignoring an error message to continue with the loop in python

It is generally a bad practice to suppress errors or exceptions without handling them, but this can be easily done like this:

try:
    # block raising an exception
except:
    pass # doing nothing on exception

This can obviously be used in any other control statement, such as a loop:

for i in xrange(0,960):
    try:
        ... run your code
    except:
        pass

How to ignore exceptions and proceed with whole blocks (multiple lines) in python?

This can be achieved with the fuckit python module.

Here is the code modified from your example:

#!/usr/bin/env python3
import fuckit

def one():
    raise Exception
    print( 'one' )
def two():
    print( 'two' )

@fuckit
def helper():
    one()
    two()

helper()

And an example execution:

user@disp3221:~$ sudo python3 -m pip install fuckit
Collecting fuckit
  Downloading https://files.pythonhosted.org/packages/cc/f4/0952081f9e52866f4a520e2d92d27ddf34f278d37204104e4be869c6911d/fuckit-4.8.1.zip
Building wheels for collected packages: fuckit
  Running setup.py bdist_wheel for fuckit ... done
  Stored in directory: /root/.cache/pip/wheels/a9/24/e6/a3e32536d1b2975c23ac9f6f1bdbc591d7b968e5e0ce6b4a4f
Successfully built fuckit
Installing collected packages: fuckit
Successfully installed fuckit-4.8.1
user@disp3221:~$ 

user@disp3221:~$ ./test.py 
two
user@disp3221:~$ 

python ignore whichever line that causes error and continue running the code after that line

What you want to do (try with restart) is not possible in Python. Lisp can do it (http://www.gigamonkeys.com/book/beyond-exception-handling-conditions-and-restarts.html), and you can implement it in Scheme using call/cc.

Python ignore and skip error line, and continue with the next line

This means that you are successfully catching an error and going to the condition in except statement and as a result your data is never loaded and the variable data is never defined. And then when you try to save data to csv, this triggers an error.

What you should do instead is to put your to_csv statement inside try-except as well:

import simplejson
import pandas as pd
with open('/tmp/test.json') as f:
    try:
        data = pd.DataFrame(simplejson.loads(line) for line in f)
        data.to_csv('/tmp/data.csv')
    except Exception as e:
        pass

Also, it is a horrible anti-pattern in Python to do except Exception as e: pass. This will result in the code that is nigh impossible to debug because you are catching every single error that might happen and not specifically the error you expect to happen. When you do this you should either log the full error stack or print it to console to be aware of what exact error you are catching:

    try:
        data = pd.DataFrame(simplejson.loads(line) for line in f)
    except Exception as e:
        err = str(e)
        print(err)        

Or you should be catching a specific error that you expect to happen here:

    try:
        data = pd.DataFrame(simplejson.loads(line) for line in f)
    except FileNotFoundError:
        pass

Ignore exception in Python

pass is the keyword you are looking for.

Python ignore all errors and continue running

You can catch errors and ignore them (if it makes sense). eg if the call foo.bar() could cause an error use

try:
    foo.bar()
except: #catch everything, should generally be avoided.
    #what should happen when an error occurs

If you only want to ignore a certain type of error use (recommended) (python 2)

try:
    foo.bar()
except <ERROR TO IGNORE>, e:
    #what should happen when an error occurs

or (python 3)

try:
    foo.bar()
except <ERROR TO IGNORE> as e:
    #what should happen when an error occurs

See the Python documentation on handling exceptions for more information.

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