reduceRight wrong example?
alizhdanov opened this issue · comments
Hello,
I'm not sure, but in find items -> one item:
reduce returns sum of the array, as I'd expect, while reduceRight 'flatten' arrays. Shouldn't it be also sum?
They're using different demo functions, and their return values are consistent with those functions. Returning the sum is just a common example use case for [].reduce.
[].reduce starts at the beginning of the array and works its way to the end. [].reduceRight starts at the end and works its way to the beginning. I think the example for [].reduceRight used in the pen might be mildly confusing for those still learning since it reduces nested arrays. Here's an example of both using the same function; note how the output differs:
['a', 'b', 'c', 'd'].reduce((current, carry) => current+carry); // ➡ abcd
['a', 'b', 'c', 'd'].reduceRight((current, carry) => current+carry); // ➡ dcba
Yeah @QWp6t you're right, I should make that a little more clear and easy to understand for beginners, since that's who this resource is for.
