JS Promise - instantly retrieve some data from a function that returns a Promise

Question

Can anyone recommend a pattern for instantly retrieving data from a function that returns a Promise?

My (simplified) example is an AJAX preloader:

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Answer 1

The method I am currently using is as follows:

var optionalReturnsObject = {};
functionThatReturnsPromise(dataToSend, optionalReturnsObject ).then(doStuffOnAsyncComplete);
console.log("Some instant data has been returned here:", optionalReturnsObject ); 

For me, the advantage of this is that another member of my team can use this in a simple way:

functionThatReturnsPromise(data).then(...);

And not need to worry about the returns object. An advanced user can see from the definitions what is going on.