Contents

prefer_is_not_operator

Contents

Prefer is! operator.

This rule is available as of Dart 2.7.

Rule sets: recommended, flutter

This rule has a quick fix available.

Details

#

When checking if an object is not of a specified type, it is preferable to use the 'is!' operator.

BAD:

dart
if (!(foo is Foo)) {
  ...
}

GOOD:

dart
if (foo is! Foo) {
  ...
}

Usage

#

To enable the prefer_is_not_operator rule, add prefer_is_not_operator under linter > rules in your analysis_options.yaml file:

analysis_options.yaml
yaml
linter:
  rules:
    - prefer_is_not_operator