Keyword:
| "break"
| "case"
| "catch"
| "class"
| "const"
| "continue"
| "debugger"
| "default"
| "delete"
| "do"
| "else"
| "enum"
| "export"
| "extends"
| "false"
| "finally"
| "for"
| "function"
| "if"
| "import"
| "in"
| "instanceof"
| "new"
| "null"
| "return"
| "super"
| "switch"
| "this"
| "throw"
| "true"
| "try"
| "typeof"
| "var"
| "void"
| "while"
| "with"