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atomic_grouping

⚡ Prevent Backtracking with Atomic Groups​

Wrap subpatterns in atomic groups (?>...) to forbid backtracking into them, eliminating catastrophic backtracking in complex patterns. This ensures once the engine leaves an atomic group, it won't revisit it, boosting performance.

str = 'a' * 30 + '!'
# Vulnerable to backtracking
regexp1 = /(a+)+!/
# Optimized with atomic group
regexp2 = /(?>a+)+!/
# regexp1.match(str) might be slow; regexp2.match(str) is instant