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avoid-dynamic

added in: 1.6.0
warning
Free+
preset: recommended

Warns when the dynamic type is used as a variable type in a declaration, return type of a function, etc.

Using dynamic is considered unsafe since it can easily result in runtime errors.

info

Using the dynamic type for a Map<> is considered fine, since there is no better way to declare a type of a JSON payload.

Example​

❌ Bad:

dynamic x = 10; // LINT: Avoid 'dynamic' types. Try replacing it with a different type.

// LINT: Avoid 'dynamic' types. Try replacing it with a different type.
String concat(dynamic a, dynamic b) {
  return a + b;
}

(dynamic,) _getValue() => (null, ); // LINT: Avoid 'dynamic' types. Try replacing it with a different type.

✅ Good:

int x = 10;

final x = 10;

String concat(String a, String b) {
  return a + b;
}

(int?,) _getValue() => (null, );

Additional Resources​