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javascriptreturnsettimeoutreturn-value

Get return value from setTimeout

I just want to get the return value from setTimeout but what I get is a whole text format of the function?

function x () {
    setTimeout(y = function () {
        return 'done';
    }, 1000);
    return y;
}

console.log(x());
Solution

  • You need to use Promises for this. They are available in ES6 but can be polyfilled quite easily:

    function x() {
   return new Promise((resolve, reject) => {
     setTimeout(() => {
       resolve('done!');
     });
   });
}

x().then((done) => {
  console.log(done); // --> 'done!'
});

    With async/await in ES2017 it becomes nicer if inside an async function:

    async function() {
  const result = await x();
  console.log(result); // --> 'done!';
}