ask help about raise, thank u

[John Machin]

"dongkui" <dongkui at huawei.com> wrote in message news:<mailman.1014686626.31452.python-list at python.org>...
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> --

After running the above through
repr(base64.decodestring(the_above_guff)) and wrapping lines at 40
columns:

'pls give me one example about raise whi
ch have three para, and the third para i
s traceback obj\r\n\r\nlike \r\nraise "a
", "b", c #c as traceback object\r\n\r\n
thank u\r\n'

Further translation:
para -> paragraph? No
para -> paratrooper? I see no "fee fi fo fum" material here.
para -> parameter -> argument? Aha! 

Disclaimer: This is how I think the third arg is meant to be used; I
have never
actually had to do this in practice.

try:
   some code which may explode
except:
   exc, data, tb = sys.exc_info()
   if I_can_handle_this(exc):
      handle_it(exc, data)
   else:
      # re-raise the exception, with traceback giving the *original*
      # source of the problem (somewhere inside the 'try' suite),
      # not the 'raise' statement
      raise exc, data, tb

Also, you would need to heed the warning in the documentation for
sys.exc_info()about circular references caused by assigning the
traceback to a local variable.

Hope this helps,
John