[ACCEPTED]-For python is there a way to print variables scope from context where exception happens?-exception

Accepted answer

Score: 21

You can use the function sys.exc_info() to get the last 8 exception that occurred in the current thread 7 in you except clause. This will be a tuple 6 of exception type, exception instance and 5 traceback. The traceback is a linked list 4 of frame. This is what is used to print 3 the backtrace by the interpreter. It does 2 contains the local dictionnary.

So you can 1 do:

import sys

def f():
    a = 1
    b = 2
    1/0

try:
    f()
except:
    exc_type, exc_value, tb = sys.exc_info()
    if tb is not None:
        prev = tb
        curr = tb.tb_next
        while curr is not None:
            prev = curr
            curr = curr.tb_next
        print prev.tb_frame.f_locals

Score: 7

You have to first extract traceback, in 4 your example something like this would print 3 it:

except:
    print sys.exc_traceback.tb_next.tb_frame.f_locals

I'm not sure about the tb_next, I would 2 guess you have to go through the complete 1 traceback, so something like this (untested):

except:
    tb_last = sys.exc_traceback
    while tb_last.tb_next:
        tb_last = tb_last.tb_next
    print tb_last.tb_frame.f_locals

Score: 3

Perhaps you're looking for locals() and globals()?

Score: 1

Depending on what you need, there are 2 4 general best practices.

Just print the variables with minimal code edits

Have a look at some 3 related packages. For simple usage you might 2 pick traceback-with-variables (pip install traceback-with-variables), here is it's postcard

Or try tbvaccine, or 1 better-exceptions, or any other package

Programmatically access variables to use them in your code

Use inspect module

except ... as ...:
    x = inspect.trace()[-1][0].f_locals['x']

Source: stackoverflow.com

[ACCEPTED]-For python is there a way to print variables scope from context where exception happens?-exception

The "correct" way to define an exception in Python without PyLint complaining

Python urllib2 URLError HTTP status code.

Tracing an ignored exception in Python?

Python raise with two parameters

SQLAlchemy check before insert in Python

Is there a built-in Python Exception for validation of function input?

save Exceptions to file in python

OSError: Directory not empty raised, how to fix?

I get "TypeError: exceptions must derive from BaseException" even though I did define it

when writing to csv file writerow fails with UnicodeEncodeError