Array.from() vs spread syntax

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Spread element or syntax (note that it’s not an operator) works only with objects that are iterable (i.e. implement the @@iterator method). Array.from() works also on array-like objects which are not iterable (i.e. objects that have indexed elements and a length property).

See this example:

const arrayLikeObject = { 0: 'a', 1: 'b', length: 2 };

// This logs ['a', 'b']
console.log(Array.from(arrayLikeObject));

// This throws TypeError: arrayLikeObject[Symbol.iterator] is not a function
console.log([...arrayLikeObject]);

Also, if you just want to convert something to an array, I think it’s better to use Array.from() because it’s more readable. Spread elements are useful for example when you want to concatenate multiple arrays (['a', 'b', ...someArray, ...someOtherArray]).

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