//// [interfaceWithMultipleBaseTypes2.ts] interface Base { x: { a?: string; b: string; } } interface Base2 { x: { b: string; c?: number; } } interface Derived extends Base, Base2 { x: { b: string } } interface Derived2 extends Base, Base2 { // error x: { a: number; b: string } } interface Derived3 extends Base, Base2 { x: { a: string; b: string } } //// [interfaceWithMultipleBaseTypes2.js]