额。。。这函数有什么特别的么 - CNode技术社区

> var a = Promise.resolve
undefined
> a(1)
TypeError: a is not a function
 at resolve (native)
 at repl:1:1
 at REPLServer.defaultEval (repl.js:248:27)
 at bound (domain.js:280:14)
 at REPLServer.runBound [as eval] (domain.js:293:12)
 at REPLServer.<anonymous> (repl.js:412:12)
 at emitOne (events.js:82:20)
 at REPLServer.emit (events.js:169:7)
 at REPLServer.Interface._onLine (readline.js:210:10)
 at REPLServer.Interface._line (readline.js:549:8)

没特别,只是这样调用并不是以对象的方法的方式调用,上下文丢了。 这样:

> var a = Promise.resolve
undefined
> a.call(Promise, 2)
Promise { 2 }