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a|bAlternation with |: a|bAlternationFormal RE✨ Emoji Combos

L(a|b) = {a, b}. Alternation is the union of two languages.

✓ Accepts

ab

✗ Rejects

εabcba

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Regular Expression Pattern

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Annotation

Unable to parse pattern

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gglobal: Don't return after first match

mmultiline: ^ and $ match start/end of each line

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