prefer_is_not_operator
Prefer is! operator.
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) {
...
}
Enable
#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
If you're instead using the YAML map syntax to configure linter rules, add prefer_is_not_operator: true
under linter > rules:
analysis_options.yaml
yaml
linter:
rules:
prefer_is_not_operator: true
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Provide details Unless stated otherwise, the documentation on this site reflects Dart 3.8.1. Page last updated on 2025-03-07. View source or report an issue.