The 'super' keyword can't be used in an extension because an extension doesn't have a superclassDRT-W1635
The analyzer produces this diagnostic when a member declared inside an
extension uses the super
keyword . Extensions aren't classes and don't
have superclasses, so the super
keyword serves no purpose.
Example
The following code produces this diagnostic because super
can't be used
in an extension:
extension E on Object {
String get displayString => super.toString();
}
Common fixes
Remove the super
keyword :
extension E on Object {
String get displayString => toString();
}