super_formal_parameter_without_associated_positional

No associated positional super constructor parameter.

The analyzer produces this diagnostic when there's a positional super parameter in a constructor and the implicitly or explicitly invoked super constructor doesn't have a positional parameter at the corresponding index.

Positional super parameters are associated with positional parameters in the super constructor by their index. That is, the first super parameter is associated with the first positional parameter in the super constructor, the second with the second, and so on.

The following code produces this diagnostic because the constructor in B has a positional super parameter, but there's no positional parameter in the super constructor in A:

class A {
  A({int? x});
}

class B extends A {
  B(super.x);
}

The following code produces this diagnostic because the constructor in B has two positional super parameters, but there's only one positional parameter in the super constructor in A, which means that there's no corresponding parameter for y:

class A {
  A(int x);
}

class B extends A {
  B(super.x, super.y);
}

If the super constructor should have a positional parameter corresponding to the super parameter, then update the super constructor appropriately:

class A {
  A(int x, int y);
}

class B extends A {
  B(super.x, super.y);
}

If the super constructor is correct, or can't be changed, then convert the super parameter into a normal parameter:

class A {
  A(int x);
}

class B extends A {
  B(super.x, int y);
}

Unless stated otherwise, the documentation on this site reflects Dart 3.8.0. Page last updated on 2025-05-08. View source or report an issue.