b.ts(1,12): error TS6133: 'T' is declared but its value is never read.


==== a.ts (0 errors) ====
    class C<T> { }
    
==== b.ts (1 errors) ====
    interface C<T> { }
               ~~~
!!! error TS6133: 'T' is declared but its value is never read.