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a+b⚠ Formal + vs programming + quantifiervs Programming RegexFormal RE✨ Emoji Combos

Programming regex: a+b matches "one-or-more a's followed by b" (ab, aab, aaab). Formal RE: a+b ≡ a|b = {a, b}. Completely different semantics.

✓ Accepts
ab
✗ Rejects
εabaabaa
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