tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck54.ts(3,11): error TS2504: No best common type exists among yield expressions. ==== tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck54.ts (1 errors) ==== class Foo { x: number } class Baz { z: number } function* g() { ~ !!! error TS2504: No best common type exists among yield expressions. yield* [new Foo]; yield* [new Baz]; }