tests/cases/compiler/undefinedTypeArgument2.ts(4,92): error TS2304: Cannot find name 'R'. tests/cases/compiler/undefinedTypeArgument2.ts(4,102): error TS2304: Cannot find name 'R'. ==== tests/cases/compiler/undefinedTypeArgument2.ts (2 errors) ==== // once caused stack overflow interface Query { selectMany(selector: (item: T) => U[]): Query; selectMany(arraySelector: (item: T) => U[], resultSelector: (outer: T, inner: U) => R): Query; ~ !!! error TS2304: Cannot find name 'R'. ~ !!! error TS2304: Cannot find name 'R'. }