Why does bool(xml.etree.ElementTree.Element) evaluate to False?

by

As it turns out, Element objects are considered a False value if they have no children.

I found this in the source:

def __nonzero__(self):
    warnings.warn(
        "The behavior of this method will change in future versions.  "
        "Use specific 'len(elem)' or 'elem is not None' test instead.",
        FutureWarning, stacklevel=2
        )
    return len(self._children) != 0 # emulate old behaviour, for now

Even the inline comment agrees with you — this behavior is iffy 😉

More Related Contents:

  1. Truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all()
  2. Logical operators for Boolean indexing in Pandas
  3. Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
  4. Parsing boolean values with argparse
  5. Converting from a string to boolean in Python?
  6. Why is bool a subclass of int?
  7. Comparing boolean and int using isinstance
  8. Python’s in (__contains__) operator returns a bool whose value is neither True nor False
  9. Comparing previous row values in Pandas DataFrame
  10. Defining “boolness” of a class in python
  11. What is the motivation for the “or” operator to not return a bool?
  12. Python AND operator on two boolean lists – how?
  13. Why is ‘True == not False’ a SyntaxError?
  14. overriding bool() for custom class [duplicate]
  15. Boolean value of objects in Python
  16. Why do ‘and’ & ‘or’ return operands in Python?
  17. Python Bool and int comparison and indexing on list with boolean values
  18. Python: False vs 0
  19. Why does “a == x or y or z” always evaluate to True? How can I compare “a” to all of those?
  20. Getting a list of indices where pandas boolean series is True
  21. Empty list boolean value
  22. Counting the number of True Booleans in a Python List
  23. Convert Pandas series containing string to boolean
  24. Filtering pandas dataframe with multiple Boolean columns
  25. What are the differences between bool() and operator.truth()?
  26. User input boolean in python
  27. How do I use a Boolean in Python?
  28. Convert True/False value read from file to boolean
  29. Python – logical evaluation order in “if” statement
  30. Select elements of numpy array via boolean mask array

Leave a Comment