const_with_non_constant_argument

Arguments of a constant creation must be constant expressions.

The analyzer produces this diagnostic when a const constructor is invoked with an argument that isn't a constant expression.

The following code produces this diagnostic because i isn't a constant:

class C {
  final int i;
  const C(this.i);
}
C f(int i) => const C(i);

Either make all of the arguments constant expressions, or remove the const keyword to use the non-constant form of the constructor:

class C {
  final int i;
  const C(this.i);
}
C f(int i) => C(i);

Unless stated otherwise, the documentation on this site reflects Dart 3.8.1. Page last updated on 2025-05-08. View source or report an issue.