util.promisify.custom

• 类型:<symbol> 可用于声明函数的自定义 Promisified 变体,请参阅 自定义 promise 化函数。

  \Type: <symbol> that can be used to declare custom promisified variants of functions, see Custom promisified functions.

除了可以通过 util.promisify.custom 访问外,这个符号是 全局注册,在任何环境下都可以作为 Symbol.for('nodejs.util.promisify.custom') 访问。

\In addition to being accessible through util.promisify.custom, this symbol is registered globally and can be accessed in any environment as Symbol.for('nodejs.util.promisify.custom').

例如,对于接受 (foo, onSuccessCallback, onErrorCallback) 的函数:

\For example, with a function that takes in (foo, onSuccessCallback, onErrorCallback):

const kCustomPromisifiedSymbol = Symbol.for('nodejs.util.promisify.custom');
doSomething[kCustomPromisifiedSymbol] = (foo) => {
 return new Promise((resolve, reject) => {
 doSomething(foo, resolve, reject);
 });
}; 拷贝