JavaScript Symbols Converting a symbol into a string
Example
Unlike most other JavaScript objects, symbols are not automatically converted into a string when performing concatenation.
let apple = Symbol('Apple') + ''; // throws TypeError!
Instead, they have to be explicitly converted into a string when necessary, (for example, to get a textual description of the symbol that can be used in a debug message) using the toString method or the String constructor.
const APPLE = Symbol('Apple');
let str1 = APPLE.toString(); // "Symbol(Apple)"
let str2 = String(APPLE); // "Symbol(Apple)"
