extension_ type_ implements_ disallowed_ type
Extension types can't implement '{0}'.
Description
#The analyzer produces this diagnostic when an extension type implements a type that it isn't allowed to implement.
Example
#
The following code produces this diagnostic because extension types can't
implement the type
dynamic
:
extension type A(int i) implements dynamic {}
Common fixes
#Remove the disallowed type from the implements clause:
extension type A(int i) {}
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