non_type_as_type_argument
The name '{0}' isn't a type, so it can't be used as a type argument.
Description
#The analyzer produces this diagnostic when an identifier that isn't a type is used as a type argument.
Example
#The following code produces this diagnostic because x
is a variable, not a type:
dart
var x = 0;
List<x> xList = [];
Common fixes
#Change the type argument to be a type:
dart
var x = 0;
List<int> xList = [];
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.