check if function is a generator

javascript generator yield ecmascript-6
Dima Vidmich picture Dima Vidmich · May 26, 2013 · Viewed 12.7k times · Source

I played with generators in Nodejs v0.11.2 and I'm wondering how I can check that argument to my function is generator function.

I found this way typeof f === 'function' && Object.getPrototypeOf(f) !== Object.getPrototypeOf(Function) but I'm not sure if this is good (and working in future) way.

What is your opinion about this issue?

Answer

smitt04 picture smitt04 · Mar 24, 2014

In the latest version of nodejs (I verified with v0.11.12) you can check if the constructor name is equal to GeneratorFunction. I don't know what version this came out in but it works.

function isGenerator(fn) {
    return fn.constructor.name === 'GeneratorFunction';
}

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