a very common use case for regexes is to find matches that are preceded or followed by some context. a classical example being all lines that end with ‘a’. this requirement is usually expressed with a lookahead, where upon finding an ‘a’, you look ahead to check if it’s the end of the line. in a backtracking engine, this is very easy to implement - you just duct-tape the logic that checks the next character, but in a DFA-based engine, this is impossible because you cannot report “the match is here” if the next character is not even known yet. and by the time you know the next character, the position information is lost, so you can’t report the match retroactively (well, unless the distance is fixed of course..).
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У берегов популярного среди россиян курорта появились опасные медузы08:45
While the tally in the House, 212-219, was expected to be tight, the outcome provided a clarifying snapshot of political support for, and opposition to, the U.S.-Israel military operation and Trump’s rationale for bypassing Congress, which alone has the power to declare war. At the Capitol, the conflict has quickly carried echoes of the long wars in Afghanistan and Iraq, and many Sept. 11-era veterans now serve in Congress.
В России допустили «второй Чернобыль» в Иране22:31