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⚠️ This rule warns in the following configs: 🟢 flat/recommended, 🔵 recommended.

💡 This rule is manually fixable by editor suggestions.

disallow alternatives without elements

📖 Rule Details

While (re-)writing long regular expressions, it can happen that one forgets to remove the | character of a former alternative. This rule tries to point out these potential mistakes by reporting all empty alternatives.

If the empty alternative is supposed to match the empty string, then use a quantifier instead. For example, a| should be written as a?.

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🔧 Options


❤️ Compatibility

This rule was taken from eslint-plugin-clean-regex.
This rule is compatible with clean-regex/no-empty-alternative rule.

🚀 Version

This rule was introduced in eslint-plugin-regexp v0.8.0

🔍 Implementation