extends_ non_ class
Classes can only extend other classes.
Description
#
The analyzer produces this diagnostic when an extends clause contains a
name that is declared to be something other than a class.
Example
#
The following code produces this diagnostic because f is declared to be a
function:
void f() {}
class C extends f {}
Common fixes
#
If you want the class to extend a class other than Object, then replace
the name in the extends clause with the name of that class:
void f() {}
class C extends B {}
class B {}
If you want the class to extend Object, then remove the extends clause:
void f() {}
class C {}
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Page last updated on 2025-9-1. View source or report an issue.