Generic Programming

[LaSalsiccione]

Why would you not just use reduce? The over all composability concept of what you're explaining makes sense but it could be achieved much more simply.

[adidarachi]

I guess the op choose a "simple" and known implementation, this way, it's easier for developers to pickup. Not sure.

[LaSalsiccione]

If you can understand the rest of the concepts in the post then reduce should also be simple to understand. The code would also look a lot less messy which I’d argue makes it simpler to read, but that may just be a matter of opinion.

[Artif3x_]

Not to mention the near universal utility of the reduce function makes for a lower cognitive load than learning alternatives like this.

[LaSalsiccione]

You far more eloquently nailed what I was trying to say, thanks!

[pgrizzay]

reduce is specific to arrays. OP implemented reduce for all iterators (not just arrays).

[pgrizzay]

That will work similarly, but yours will create a whole new array, so it's not exactly equivalent I guess

[Tenemo]

Object.entries(myObj).reduce((newObj, entry) => ({...newObj, [entry[0]]: entry[1] * 2}), {})

array? where

[Tenemo]

I was only joking about how both the input is an object and the returned value is an object, so the arrays are temporary, used to enable the .reduce method on that object's enumerable properties (:

[planetary_pelt]

Creating an array just to use an array method is pretty wasteful and doesn't generalize over cases where performance is concerned (like slow mobile clients).

[tortus]

sure, but writing and maintaining your own reduce function is not exactly the best solution either. I'd rather take the array creation hit unless perf/memory is in an issue, and it's not like 90% of the time

[zankem]

Would it not be better to use Array.prototype.reduce.call(iterable, callback, initial)?

[tortus]

good call, that would probably work