demo/typescript.js
function isReservedMemberName(name) {
            return name.charCodeAt(0) === 95 /* _ */ &&
                name.charCodeAt(1) === 95 /* _ */ &&
                name.charCodeAt(2) !== 95 /* _ */ &&
                name.charCodeAt(2) !== 64 /* at */;
        }
function isReservedMemberName(name) {
            return name.charCodeAt(0) === 95 /* _ */ &&
                name.charCodeAt(1) === 95 /* _ */ &&
                name.charCodeAt(2) !== 95 /* _ */ &&
                name.charCodeAt(2) !== 64 /* at */;
        }
A reserved member name starts with two underscores, but the third character cannot be an underscore or the @ symbol. A third underscore indicates an escaped form of an identifer that started with at least two underscores. The @ character indicates that the name is denoted by a well known ES Symbol instance.