require<\/span> "string_reader"<\/span><\/div>require<\/span> "state_builder"<\/span><\/div> <\/div>
class<\/span> StringMatcher<\/span><\/div> def<\/span> is_match<\/span>(<\/span>pattern<\/span>,<\/span> test_string<\/span>)<\/span><\/div> state_builder<\/span> =<\/span> StateBuilder<\/span>.<\/span>new<\/span><\/div> graph<\/span> =<\/span> state_builder<\/span>.<\/span>create_from<\/span>(<\/span>pattern<\/span>)<\/span><\/div> <\/div>
reader<\/span> =<\/span> StringReader<\/span>.<\/span>new<\/span>(<\/span>test_string<\/span>)<\/span><\/div> next_states<\/span> =<\/span> [<\/span>graph<\/span>]<\/span><\/div> while<\/span> !<\/span>reader<\/span>.<\/span>end_of_string<\/span><\/div> test_states<\/span> =<\/span> next_states<\/span><\/div> next_states<\/span> =<\/span> []<\/span><\/div> current_character<\/span> =<\/span> reader<\/span>.<\/span>read<\/span><\/div> <\/div>
test_states<\/span>.<\/span>each<\/span> do<\/span> |<\/span>state<\/span>|<\/span><\/div> state<\/span>.<\/span>transitions<\/span>.<\/span>each<\/span> do<\/span> |<\/span>transition<\/span>|<\/span><\/div> if<\/span> transition<\/span>.<\/span>can_do<\/span>(<\/span>current_character<\/span>)<\/span><\/div> next_states<\/span> <<<\/span> transition<\/span>.<\/span>destination<\/span><\/div> end<\/span><\/div> end<\/span><\/div> end<\/span><\/div> end<\/span><\/div> <\/div>
next_states<\/span>.<\/span>each<\/span> do<\/span> |<\/span>state<\/span>|<\/span><\/div> state<\/span>.<\/span>transitions<\/span>.<\/span>each<\/span> do<\/span> |<\/span>transition<\/span>|<\/span><\/div> if<\/span> transition<\/span>.<\/span>class<\/span> ==<\/span> AlwaysTransition<\/span> and<\/span> transition<\/span>.<\/span>destination<\/span>.<\/span>class<\/span> ==<\/span> TerminalState<\/span><\/div> return<\/span> true<\/span><\/div> end<\/span><\/div> end<\/span><\/div> end<\/span><\/div> <\/div>
return<\/span> false<\/span><\/div> end<\/span><\/div>end<\/span><\/div><\/pre><\/div>\n \n <\/div>\n\n