non_const_generative_enum_constructor

Generative enum constructors must be 'const'.

The analyzer produces this diagnostic when an enum declaration contains a generative constructor that isn't marked as const.

The following code produces this diagnostic because the constructor in E isn't marked as being const:

enum E {
  e;

  E();
}

Add the const keyword before the constructor:

enum E {
  e;

  const E();
}

Unless stated otherwise, the documentation on this site reflects Dart 3.7.3. Page last updated on 2025-05-08. View source or report an issue.