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Discussion on: 1 line of code: How to remove all duplicates from an Array

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Erik Waters • • Edited

I think they mean it won't behave as expected if the array contains similar objects that have different references

const originalObject = {}
const boundToOriginalObject = originalObject
const newObjectThatLooksLikeOriginal = {}
const arr = [originalObject, boundToOriginalObject, newObjectThatLooksLikeOriginal]
const dedupe = [ ...new Set(arr)]
dedupe // [{}, {}]
// deduping removes the duplicate reference but not similar objects
const mutation = {a: 1}
Object.assign(dedupe[1], mutation)
originalObject // {}
newObjectThatLooksLikeOriginal // { a: 1 }
// this proves which references remained in the deduped array prior to mutation
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It might be helpful to clarify that dedupe will remove duplicate bindings but not similar objects with a different binding