errors

tt error types.

errors.base module

The base tt exception type.

exception tt.errors.base.TtError(message, *args)

Bases: Exception

Base exception type for tt errors.

Note

This exception type should be sub-classed and is not meant to be raised explicitly.

message

A helpful message intended to be shown to the end user.

Type:str

errors.evaluation module

Exception type definitions related to expression evaluation.

exception tt.errors.evaluation.DuplicateSymbolError(message, *args)

Bases: tt.errors.evaluation.EvaluationError

An exception type for user-specified duplicate symbols.

>>> from tt import TruthTable
>>> try:
...     t = TruthTable('A or B', ordering=['A', 'A', 'B'])
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.evaluation.DuplicateSymbolError'>

exception tt.errors.evaluation.EvaluationError(message, *args)

Bases: tt.errors.base.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.

exception tt.errors.evaluation.ExtraSymbolError(message, *args)

Bases: tt.errors.evaluation.EvaluationError

An exception for a passed token that is not a parsed symbol.

>>> from tt import TruthTable
>>> try:
...     t = TruthTable('A or B', ordering=['A', 'B', 'C'])
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.evaluation.ExtraSymbolError'>

exception tt.errors.evaluation.InvalidBooleanValueError(message, *args)

Bases: tt.errors.evaluation.EvaluationError

An exception for an invalid truth value passed in evaluation.

>>> 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'>

exception tt.errors.evaluation.MissingSymbolError(message, *args)

Bases: tt.errors.evaluation.EvaluationError

An exception type for a missing token value in evaluation.

>>> from tt import BooleanExpression
>>> try:
...     b = BooleanExpression('A and B')
...     b.evaluate(A=1)
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.evaluation.MissingSymbolError'>

exception tt.errors.evaluation.NoEvaluationVariationError(message, *args)

Bases: tt.errors.evaluation.EvaluationError

An exception type for when evaluation of an expression will not vary.

>>> from tt import TruthTable
>>> try:
...     t = TruthTable('1 or 0')
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.evaluation.NoEvaluationVariationError'>

errors.generic module

Generic exception types.

exception tt.errors.generic.InvalidArgumentTypeError(message, *args)

Bases: tt.errors.base.TtError

An exception type for invalid argument types.

>>> from tt import TruthTable
>>> try:
...     t = TruthTable(7)
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.generic.InvalidArgumentTypeError'>

errors.grammar module

Exception type definitions related to expression grammar and parsing.

exception tt.errors.grammar.BadParenPositionError(message, expr_str=None, error_pos=None, *args)

Bases: tt.errors.grammar.GrammarError

An exception type for unexpected parentheses.

>>> from tt import BooleanExpression
>>> try:
...     b = BooleanExpression(') A or B')
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.grammar.BadParenPositionError'>

exception tt.errors.grammar.EmptyExpressionError(message, expr_str=None, error_pos=None, *args)

Bases: tt.errors.grammar.GrammarError

An exception type for when an empty expression is received.

>>> from tt import BooleanExpression
>>> try:
...     b = BooleanExpression('')
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.grammar.EmptyExpressionError'>

exception tt.errors.grammar.ExpressionOrderError(message, expr_str=None, error_pos=None, *args)

Bases: tt.errors.grammar.GrammarError

An exception type for unexpected operands or operators.

>>> from tt import BooleanExpression
>>> try:
...     b = BooleanExpression('A or or B')
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.grammar.ExpressionOrderError'>

exception tt.errors.grammar.GrammarError(message, expr_str=None, error_pos=None, *args)

Bases: tt.errors.base.TtError

Base type for errors that occur in the handling of expression.

Note

This exception type should be sub-classed and is not meant to be raised explicitly.

error_pos

The position in the expression where the error occurred.

Note

This may be left as None, in which case there is no specific location in the expression causing the exception.

Type:int

expr_str

The expression in which the exception occurred.

Note

This may be left as None, in which case the expression will not be propagated with the exception.

Type:str

exception tt.errors.grammar.UnbalancedParenError(message, expr_str=None, error_pos=None, *args)

Bases: tt.errors.grammar.GrammarError

An exception type for unbalanced parentheses.

>>> from tt import BooleanExpression
>>> try:
...     b = BooleanExpression('A or ((B)')
... except Exception as e:
...     print(type(e))
...
<class 'tt.errors.grammar.UnbalancedParenError'>