JS References

• Decorator
• Reflect
• Prototype

Function

// 检测 AsyncIterator/Generator
// next, return, throw
console.assert('next' in async function* () {}.prototype);
console.assert('next' in function* () {}.prototype);

(function* () {})[Symbol.toStringTag]; // GeneratorFunction
(async function* () {})[Symbol.toStringTag]; // AsyncGeneratorFunction
(async () => {})[Symbol.toStringTag]; // AsyncFunction

Symbol

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol#well-known_symbols

Symbol.toStringTag

• Object.prototype.toString()
• [object ${@@toStringTag}]