tests/cases/compiler/numericIndexerConstraint5.ts(2,5): error TS2322: Type '{ 0: Date; name: string; }' is not assignable to type '{ [name: number]: string; }'. Index signature is missing in type '{ 0: Date; name: string; }'. ==== tests/cases/compiler/numericIndexerConstraint5.ts (1 errors) ==== var x = { name: "x", 0: new Date() }; var z: { [name: number]: string } = x; ~ !!! error TS2322: Type '{ 0: Date; name: string; }' is not assignable to type '{ [name: number]: string; }'. !!! error TS2322: Index signature is missing in type '{ 0: Date; name: string; }'.