text: //// [incompatibleGenericTypes.ts]
  
  interface I1<T> {
  
    m1<U>(callback: (p: T) => U): I1<U>;
  
  }
   
  var v1: I1<boolean>;
   
  var v2: I1<number> = v1;
  
  //// [incompatibleGenericTypes.js]
  var v1;
  var v2 = v1;
  