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kotlinlang

Best way to filter a list using other list?
I want to filter a list of objects with list of ids.
As of now, I am just doing this
```ids.forEach { id -&gt;
   val person = persons.find { it.id == id}
   filteredList.add(person)
}```


```filteredList += persons.filter { it.id in ids} OR persons.filterTo(filteredList) { it.id in ids }```

if you have a mutable collection, it can be filtered in-place
```persons.retainAll { it.id in ids }```

note that both these operations are O(`persons.size` · `ids.size`); if `persons` is not small then it would be better to convert `ids` to a `Set` first