extension_declares_constructor
Extensions can't declare constructors.
Description
#The analyzer produces this diagnostic when a constructor declaration is found in an extension. It isn't valid to define a constructor because extensions aren't classes, and it isn't possible to create an instance of an extension.
Example
#The following code produces this diagnostic because there is a constructor declaration in E
:
extension E on String {
E() : super();
}
Common fixes
#Remove the constructor or replace it with a static method.
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