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Discussion on: 8 JavaScript Tips & Tricks That No One Teaches 🚀

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cubiclesocial

We can also use that to swap values fast

Swapping variables with an array isn't going to be faster (performance-wise) than just swapping the variables with the traditional method of using a temporary variable.

stackoverflow.com/questions/162016...

One of the first comments on using a temporary array is that it is roughly two times slower than a variable swap.

Javascript processes most accesses by reference. So assigning to a temporary variable doesn't copy anything but a memory address. Creating an array, on the other hand, is almost certainly going to: Hit the memory allocation pool, add two variables to the array, update the length of the array (for no good reason), then immediately extract them back out of the array, and release the array back into the memory pool. Without even having to test that, the former is obviously faster than the latter. Swapping vars happens often in software, and usually in a loop, so writing performant code vs. one-liners is more important here.

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