tests/cases/compiler/invalidConstraint1.ts(1,15): error TS2313: Constraint of a type parameter cannot reference any type parameter from the same type parameter list. ==== tests/cases/compiler/invalidConstraint1.ts (1 errors) ==== function f() { ~~~~~~~~~~~~~~~~~~ !!! error TS2313: Constraint of a type parameter cannot reference any type parameter from the same type parameter list. return undefined; } f(); // should error