tests/cases/compiler/binaryArithmatic3.ts(1,9): error TS2362: The left-hand side of an arithmetic operation must be of type 'any', 'number' or an enum type. tests/cases/compiler/binaryArithmatic3.ts(1,21): error TS2363: The right-hand side of an arithmetic operation must be of type 'any', 'number' or an enum type. ==== tests/cases/compiler/binaryArithmatic3.ts (2 errors) ==== var v = undefined | undefined; ~~~~~~~~~ !!! error TS2362: The left-hand side of an arithmetic operation must be of type 'any', 'number' or an enum type. ~~~~~~~~~ !!! error TS2363: The right-hand side of an arithmetic operation must be of type 'any', 'number' or an enum type.