JavaScript How To Convert Recursive Function With Callbacks to Use Promises

I updated one of my websites to use JavaScript promises instead of callbacks. It was pretty straightforward, but got a little tricky for a recursive function. Below is how to do the conversion update:

Recursive callback function:

function doSomething(value) {
    function callback(result) {
        console.log('Done ' + result);
    }
   
    theRecursiveFunction(value, callback);   
}

function theRecursiveFunction(value, next) { 
    if (value> 3) {
        console.log('Try again ' + value);
        theRecursiveFunction(value-1, next);
    } else {
        next(value);
    }
}

doSomething(5);


Recursive function with promises:

function doSomething(value) {
    theRecursiveFunction(value)
        .then((result) => {
            console.log('Done ' + result);
        });                                   
}

function theRecursiveFunction(value) {
    return new Promise((resolve, reject) => {
        if (value > 3) {
           console.log('Try again ' + value);
                    theRecursiveFunction(value-1)
                    .then((result) => {
                        resolve(result);
                    });
        } else {
            resolve(value);
        }
    });
}

doSomething(5);




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