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lang-js
Array.from()inArray.from(Array(26))?Array(26)is guaranteed to return an array.Array.from()is for converting something that's array-like (e.g. a NodeList) to an actual array.Array.fromis necessary because, per the docs, "[map] is invoked only for indexes of the array which have assigned values."Array(26)creates an array of length 26 containing only empty items, soArray(26).map(...)would do nothing. It's worth noting that this is very javascript-specific. In most languages, creating an array will allocate it, even if the values in the resultant array are just whatever was in already memory at those locations.