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Мужчина ворвался в прямой эфир телеканала и спустил штаны20:53
this isn’t just an academic curiosity. flip the alternation order to (ab|a)+ and suddenly PCRE matches the entire string! the | operator in backtracking engines is ordered - it’s not union, it’s “try left first”. the order of branches changes the result, which means | is not commutative. a|b and b|a can give different matches.
President Donald Trump arrives at the White House as joint US-Israeli military strikes on Iran continue. Washington, DC, on March 1st, 2026. | Photo: Getty Images