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Check if array elements are equal
JavaScript, Array · Oct 18, 2020
Checks if all elements in an array are equal.
- Use
Array.prototype.every()to check if all the elements of the array are the same as the first one. - Elements in the array are compared using the strict comparison operator, which does not account for
NaNself-inequality.
const allEqual = arr => arr.every(val => val === arr[0]);allEqual([1, 2, 3, 4, 5, 6]); // false
allEqual([1, 1, 1, 1]); // trueMore like this
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