prefer-type-over-var

added in: 1.7.0

style

🛠

Warns when a variable is declared with the var keyword instead of a type.

Although var is shorter to write, the use of this keyword makes it difficult to understand the type of the declared variable.

Example

❌ Bad:

class SomeClass {
  void method() {
    var variable = nullableMethod(); // LINT
  }
}

var topLevelVariable = nullableMethod(); // LINT

String? nullableMethod() => null;

✅ Good:

class SomeClass {
  void method() {
    String? variable = nullableMethod();
  }
}

String? topLevelVariable = nullableMethod();

String? nullableMethod() => null;