Why Does 'await is Only Valid in Async Function' Occur in JavaScript?

"await is Only Valid in Async Function" Error

In JavaScript, the await keyword is only valid within an async function. This error occurs when trying to use await in a non-async function.

Consider the following code snippet:

// lib/helper.js
var myfunction = async function (x, y) {
  return [x, y];
};
exports.myfunction = myfunction;

This code defines an asynchronous function called myfunction. In a separate file, the following code is written:

// anotherFile.js
var helper = require('./helper.js');

var start = function (a, b) {
  const result = await helper.myfunction('test', 'test');
};
exports.start = start;

This code accesses the myfunction from the helper file. However, it attempts to invoke await within the non-asynchronous start function, which raises the "await is only valid in async function" error.

To resolve this issue, the start function should be made asynchronous:

async function start(a, b) {
  const result = await helper.myfunction('test', 'test');

  console.log(result);
}

In summary, using await requires the enclosing function to be an async function. When the error specifies "await is only valid in async function," ensure that the function where await is called is correctly marked as async.

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