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avoid-keywords-in-wildcard-pattern

added in: 1.7.0
style
🛠
Dart 3.0+
Pro+
preset: recommended

Warns when a wildcard pattern has declaration keywords.

Adding keywords to wildcard patterns in unnecessary, since the wildcard value cannot be referenced or mutated.

Example​

❌ Bad:

void fn() {
  final animal = 'hello';

  final value = switch (animal) {
    // LINT: Avoid keywords in wildcard patterns. Try removing the keyword.
    final Object? _ => 'bad',

    // LINT: Avoid keywords in wildcard patterns. Try removing the keyword.
    var _ => 'bad',

    // LINT: Avoid keywords in wildcard patterns. Try removing the keyword.
    final _ => 'bad',
  };
}

✅ Good:

void fn() {
  final animal = 'hello';

  final value = switch (animal) {
    Object? _ => 'good', // Correct, no keywords
    _ => 'good',
    Object _ => 'good',
  };
}