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pythonpython-3.xminiconda

TypeError: cannot unpack non-iterable bool object using Python 3.7

Here is the full traceback:

Traceback (most recent call last):
...
  File "C:\Users\rafin\Dyna\updews-pycodes\dynadb\db.py", line 251, in read
    db, cur = connect(host=host, connection=connection,
TypeError: cannot unpack non-iterable bool object

Here is the whole db.py script which is the source of the TypeError if it helps

Please tell me if there's any additional information that I could provide.

Solution

  • This error comes from doing the equivalent of the following:

    x, y = True

TypeError: cannot unpack non-iterable bool object

    On the right-hand side of the assignment, you have a boolean, True. The interpreter has no way to split that up into 2 values as required by the left-hand side of the assignment, so it gives an error.

    Your connect function returns a Connection object and a Cursor cursor object when connection succeeds, but returns the boolean value False when connection fails, leading you to the above error.

    It's generally considered a design problem to return different shapes of results from a function. Raise an exception on failure or return the same shape on all code paths, say (True, connection, cursor) on success and (False, None, None) on failure.

    Good luck! :)