Question

This is a question I have wondered about for quite some time, yet I have never found a suitable solution. If I run a script and I come across, let’s say an IndexError, python prints the line, location and quick description of the error and exits. Is it possible to automatically start pdb when an error is encountered? I am not against having an extra import statement at the top of the file, nor a few extra lines of code.

Answer 1

You can use traceback.print_exc to print the exceptions traceback. Then use sys.exc_info to extract the traceback and finally call pdb.post_mortem with that traceback

import pdb, traceback, sys  def bombs():     a = []     print a[0]  if __name__ == '__main__':     try:         bombs()     except:         extype, value, tb = sys.exc_info()         traceback.print_exc()         pdb.post_mortem(tb) 

If you want to start an interactive command line with code.interact using the locals of the frame where the exception originated you can do

import traceback, sys, code  def bombs():     a = []     print a[0]  if __name__ == '__main__':     try:         bombs()     except:         type, value, tb = sys.exc_info()         traceback.print_exc()         last_frame = lambda tb=tb: last_frame(tb.tb_next) if tb.tb_next else tb         frame = last_frame().tb_frame         ns = dict(frame.f_globals)         ns.update(frame.f_locals)         code.interact(local=ns)