the teacher said that the spread operator is on the right side of the "=" This seems like a really bad way of describing things. The "rest" operator appears inside of parameter lists (like in your example), or inside a destructuring declaration (like let [a, ...b] = [1, 2, 3]). It occurs where variables are being created. The "spread" operator is used when you want to "spread"/flatten the data you have into another structure. That can occur inside argument lists (some_func(...data)), or inside of something like an array ([1, 2, 3, ...someData, 4, 5, 6]). In both cases, the placement of the = is irrelevant. More on reddit.com

I think its very confusing More on reddit.com

Spread Operators for Arrays The core piece to know is the ... syntax. This is the spread operator, and it essentially takes either an array or an object and expands it into its set of items. Careful here. Spreading into an array only works on objects if that object is iterable. [...{}] // Error, not iterable [...{ *[Symbol.iterator](){} }] // ok Array objects are inherently iterable so are ok, that is unless you break them :P const arr = [] arr[Symbol.iterator] = null [...arr] // Error, not iterable This does not apply to spreading in objects since that maps to Object.assign() which only cares about own enumerable properties. {...{}} // ok (doesn't have to be iterable) More on reddit.com

Thank you for sharing this. You made my day and helped me learn something really useful.

Have a nice day :)

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