[removed] Difference between .forEach() and .map()

Question

I know that there were a lot of topics like this. And I know the basics: .forEach() operates on original array and .map() on the new one.

I

Answer 1

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║                ║ foreach                             ║ map                                   ║
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║ Functionality  ║ Performs given operation on each    ║ Performs given "transformation" on    ║
║                ║ element of the array                ║ "copy" of each element                ║
╠————————————————╫—————————————————————————————————————╫———————————————————————————————————————╢
║ Return value   ║ Returns undefined                   ║ Returns new array with tranformed     ║
║                ║                                     ║ elements leaving back original array  ║
║                ║                                     ║ unchanged                             ║
╠————————————————╫—————————————————————————————————————╫———————————————————————————————————————╢
║ Preferrable    ║ Performing non—transformation like  ║ Obtaining array containing output of  ║
║ usage scenario ║ processing on each element.         ║ some processing done on each element  ║
║ and example    ║                                     ║ of the array.                         ║
║                ║ For example, saving all elements in ║                                       ║
║                ║ the database                        ║ For example, obtaining array of       ║
║                ║                                     ║ lengths of each string in the         ║
║                ║                                     ║ array                                 ║
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