in RE#, we solve this by encoding the context information in the state itself. below, you can see the state machine for the regex ab(?=cd), which matches an ‘ab’ only if it’s followed by a ‘cd’. encoded in the final state, is the information that the match actually happened two characters ago.
To bridge the gap between metaprogramming and the type
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Pour diffusion immédiate | 25 février 2026
Андрей Ставицкий (Редактор отдела «Наука и техника»)
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