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Comment by venning | Hacker News Reader

Not mentioned here, but worth considering: Lodash's forEach works on "array-likes" not just proper Arrays.

It works on `arguments`, it works on strings (iterating through characters), it works on objects (passing the key as the iteratee's second parameter in place of an index value), it works on HTMLCollection pseudo-arrays. It also doesn't throw on null or undefined.

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As of ES2015 you can convert an iterable like HTMLCollection into a regular array by using the spread syntax:

    [...iterable]

That, or `Array.from`. You can even create an array from a string:

    Array.from('string')
    [...'string']

You have always been able to convert them with:

  Array.prototype.slice.call(htmlCollection);

Which has been the canonical way to cast them. But it will still throw on null or undefined.

A simple Object.keys(str|obj|etc...) call on your iterating object makes the other functions work on those data types too.

Lodash may be fast, but recently I've been avoiding the basic "lodash function with native js equivalent" for one particular reason: stepping into js native functions when debugging (node inspect) is a breeze, and a complete nightmare when using lodash.

No. Object.keys() does not allow iteration on strings or `arguments` or HTMLCollections. It only returns an array of indices not values. You can call Array#forEach() on the resultant array, but you'd need another iteratee signature to process them than you would for a proper forEach or for Lodash's method, or you'd have to dereference each element manually. At that point, you might as well run a for loop, since the code will be nearly identical.

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