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.

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Answer 1

You define such a function (doc here):

def raiseErr():
   for f in inspect.stack(): print '-', inspect.getframeinfo(f[0])

and call it from your modules so:

raiseErr()

The function raiseErr will print info about the place you called it.

More elaborate, you can do so:

import inspect, traceback
A = [inspect.getframeinfo(f[0]) for f in inspect.stack()]
print "traceback structure fields:", filter(lambda s: s[0] != '_', dir(A[0]))
print A[0].filename, A[0].lineno
for f in inspect.stack():
    F = inspect.getframeinfo(f[0])
    print '-', F.filename, F.lineno, '\t', F.code_context[0].strip()

Other possibility is to define this function:

def tr():
    print '* - '*10,
    print sys._getframe(1).f_code.co_name

And call it in the place where you want the trace. If you want all the trace, make an iterator from 1 up in _getframe(1).