How can you programmatically inspect the stack trace of an exception in Python?

Question

When an exception occurs in Python, can you inspect the stack? Can you determine its depth? I\'ve looked at the traceback module, but I can\'t figure out how to use it.

<

Answer 1

I like the traceback module.

You can get a traceback object using sys.exc_info(). Then you can use that object to get a list preprocessed list of traceback entries using traceback.extract_tb(). Then you can get a readable list using traceback.format_list() as follows:

import sys
import traceback, inspect

try:
    f = open("nonExistant file",'r')
except:
    (exc_type, exc_value, exc_traceback) = sys.exc_info()
    #print exception type
    print exc_type
    tb_list = traceback.extract_tb(sys.exc_info()[2])
    tb_list = traceback.format_list(tb_list)
    for elt in tb_list:
        print elt
        #Do any processing you need here.

See the sys Module: http://docs.python.org/library/sys.html

and the traceback Module: http://docs.python.org/library/traceback.html