como usar o castArray no javascript es6

Casts the provided value as an array if it’s not one.

Use Array.prototype.isArray() to determine if val is an array and return it as-is or encapsulated in an array accordingly.

const castArray = val => (Array.isArray(val) ? val : [val]);

castArray('foo'); // ['foo']
castArray([1]); // [1]

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