You're getting "undefined" because this execution will return undefined to the console (It Happens…

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const promise = new Promise((resolve, reject) => {
  console.log(1);
  setTimeout(() => {
    console.log("timerStart");
    resolve("success");
    console.log("timerEnd");
  }, 0);
  console.log(2);
});

promise.then((res) => {
  console.log(res);
});

console.log(4);
Can You Answer This Senior Level JavaScript Promise Interview Question?
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Shuai Li
Vamsi Krishna Kodimela
·Follow
Aug 19, 2024
--
You're getting "undefined" because this execution will return undefined to the console (It Happens only if you execute in the browser Console). Try running it as a node script; you'll get the output:
1
2
4
timerStart
timerEnd
success
--
--
Written by Vamsi Krishna Kodimela634 Followers
·151 Following
Responses (1)
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