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Bug: NFA doesn't support non-string states

See original GitHub issue

from automata.fa.nfa import NFA

nfa = NFA(
    states={0},
    input_symbols={'0'},
    transitions={0: {}},
    initial_state=0,
    final_states=set()
)

print(nfa.accepts_input(''))

I would expect this to print False, because the NFA has no accepting states. Instead, it throws this error:

File "/usr/local/lib/python3.8/site-packages/automata/base/automaton.py", line 41, in accepts_input
    self.read_input(input_str)
  File "/usr/local/lib/python3.8/site-packages/automata/base/automaton.py", line 34, in read_input
    for config in validation_generator:
  File "/usr/local/lib/python3.8/site-packages/automata/fa/nfa.py", line 120, in read_input_stepwise
    self._check_for_input_rejection(current_states)
  File "/usr/local/lib/python3.8/site-packages/automata/fa/nfa.py", line 104, in _check_for_input_rejection
    ', '.join(current_states)))
TypeError: sequence item 0: expected str instance, int found

Would it be possible to replace ', '.join(current_states) with ', '.join(str(state) for state in current_states), or something along those lines?

Issue Analytics

State:
Created 3 years ago
Comments:8 (5 by maintainers)

Top GitHub Comments

1reaction

caleb531commented, Aug 17, 2022

@maryembenali Yeah, I think you’re describing a separate issue than this ticket. Can you please create a separate issue so I can look into it? Please include the NFA code you are using, if possible—anything that might help me reproduce the issue on my end.

1reaction

caleb531commented, Mar 20, 2021

@jasonxia17 I think it’s safe to close this issue since I am confident the new tests cover all cases for the bug. Thank you for reporting it!