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javascriptpromisees6-promise

Javascript return same value in then and catch

In JS, let's say I call a promise in a 'fire and forget' way. I don't care if it was successful or not, and I don't care what it returns as I want to return the same value anyways.

I can call

return myPromise().then(() => foo).catch(() => foo);

Is there a way to not repeat then then and catch parts?

What I've tried

I thought about using finally, thinking that it will take what finally returns (similar to what Java does by taking the return value of the finally block) : return myPromise().finally(() => foo); But it turns out it didn't do what I expected. According to mdn, this return value will be used to reject in case the original promise rejected.

Solution

  • You could have a look at Promise.allSettled if you're targeting newer browsers or Node.js versions.

    This function will return a Promise that resolves whether or not the passed Promise resolves or rejects.

      
function foo(results) { 
    console.log('foo():', ...results)
}

// Success path
Promise.allSettled([Promise.resolve('Yay')]).then(foo)

// Failure path
Promise.allSettled([Promise.reject('Doh')]).then(foo)
    .as-console-wrapper { max-height: 100% !important; }