Questions tagged [traceback]

A traceback is a report of the actions leading up to a run-time error in the execution of a program. For example, the following traceback:

Traceback (most recent call last):
  File "convert.py", line 23, in <module>
    display(literal_eval(sys.argv[1]), *sys.argv[2:])
  File "convert.py", line 16, in display
    result = convert(quantity, from_unit, to_unit)
  File "convert.py", line 10, in convert
    conversion = CONVERSIONS[from_unit, to_unit]
KeyError: ('cm', 'inch')

shows that in the Python program convert.py, the function display() was called, which in turn called the function convert(), which attempted to look up a nonexistent item with the key ('cm', 'inch') in the dictionary CONVERSIONS.

Reporting the actions leading up to an error, rather than just the line on which the error occurred, can assist in debugging a faulty program.