Lodash union of arrays of mongoose ObjectId

node.js mongoose union lodash

If you're looking at two different arrays with strings of 'objectIDs' you can use concat and then uniq to remove the duplicates. Don't forget to run valueOf at the end of your Lodash chain to call it to execute.

Below is an illustrative example:

let array1 = ['42142141221421d', '9999'];let array2 = ['s421421412412fef3', '42142141221421d', '1234'];const res = _(array1)       .concat(array2)       .uniq()       .valueOf();console.log(res);

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