JavaScript, async and await keywords
Magus
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await
can only be used in an async
function
You can't use await
outside of an async
function. The code will just crash if you try. When you are coding in a NodeJS environment, that means that you can't use await
in the body directly. You have to use a function like this:
Use a main function
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async function job() {
return 'test';
}
async function main() {
console.log(await job());
}
// Don't forget to call your main
main();
Unhandled error
In NodeJS 8+, an unhandled error will trigger a warning. But the warning says that in later versions, it will be changed to a crash. You can see this warning with the following code:
Unhandled error
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async function job() {
throw new Error('error');
}
job(); // The promise returned by the job function is in error but no one handle it
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