tests/cases/compiler/letAsIdentifierInStrictMode.ts(2,5): error TS1212: Identifier expected. 'let' is a reserved word in strict mode. tests/cases/compiler/letAsIdentifierInStrictMode.ts(3,5): error TS2300: Duplicate identifier 'a'. tests/cases/compiler/letAsIdentifierInStrictMode.ts(4,1): error TS1212: Identifier expected. 'let' is a reserved word in strict mode. tests/cases/compiler/letAsIdentifierInStrictMode.ts(6,1): error TS2300: Duplicate identifier 'a'. ==== tests/cases/compiler/letAsIdentifierInStrictMode.ts (4 errors) ==== "use strict"; var let = 10; ~~~ !!! error TS1212: Identifier expected. 'let' is a reserved word in strict mode. var a = 10; ~ !!! error TS2300: Duplicate identifier 'a'. let = 30; ~~~ !!! error TS1212: Identifier expected. 'let' is a reserved word in strict mode. let a; ~ !!! error TS2300: Duplicate identifier 'a'.