To get duplicate values from an array with JavaScript Lodash, we can use the filter and includes methods.
For instance, we write
const dups = _.filter(arr, (val, i, iteratee) =>
_.includes(iteratee, val, i + 1)
);
to call filter with arr and a callback that calls includes to check if val is included in the arr array itself from index i + 1 and oin.
iteratee is the arr array.
An array with the duplicates is returned.
