#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# exceptions.py

"""PyPhi exceptions."""


class StateUnreachableError(ValueError):
    """The current state cannot be reached from any previous state."""

    def __init__(self, state):
        self.state = state
        msg = 'The state {} cannot be reached in the given TPM.'
        super().__init__(msg.format(state))


class ConditionallyDependentError(ValueError):
    """The TPM is conditionally dependent."""


class JSONVersionError(ValueError):
    """JSON was serialized with a different version of PyPhi."""


class WrongDirectionError(ValueError):
    """The wrong direction was provided."""