pocketpy/docs/modules/traceback.md

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icon: package

label: traceback

traceback

Report the exception currently being handled by a Python except block.

Function	Behavior
print_exc()	Print the active exception and traceback; return None.
format_exc()	Return the traceback string, or None when no exception is being handled.

import traceback

def describe_error():
    return traceback.format_exc()

try:
    raise ValueError('invalid level')
except ValueError:
    message = describe_error()
    assert 'ValueError: invalid level' in message
    print(message)

assert traceback.format_exc() is None

Both functions work in helper functions called from an exception handler and inside nested try blocks. Outside a handler, print_exc() prints nothing. There are no limit, file, or chain parameters.

For failures returned to C rather than handled by Python, use py_printexc() or py_formatexc(); see host exception handling.