Source code for tt.errors.evaluation
"""Exception type definitions related to expression evaluation."""
from .base import TtError
[docs]class EvaluationError(TtError):
"""An exception type for errors occurring in expression evaluation.
.. note::
This exception type should be sub-classed and is not meant to be raised
explicitly.
"""
[docs]class InvalidBooleanValueError(EvaluationError):
"""An exception for an invalid truth or don't care value passed.
.. code-block:: python
>>> from tt import BooleanExpression
>>> try:
... b = BooleanExpression('A or B')
... b.evaluate(A=1, B='brian')
... except Exception as e:
... print(type(e))
...
<class 'tt.errors.evaluation.InvalidBooleanValueError'>
"""
[docs]class NoEvaluationVariationError(EvaluationError):
"""An exception type for when evaluation of an expression will not vary.
.. code-block:: python
>>> from tt import TruthTable
>>> try:
... t = TruthTable('1 or 0')
... except Exception as e:
... print(type(e))
...
<class 'tt.errors.evaluation.NoEvaluationVariationError'>
"""