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Dartでリストからnullを削除する方法(Swift, Kotlin比較つき)

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状況

例えば以下のような配列があって、nullを排除したい

final list = [1,null,3,null,5]

Dartにはビルトインの高階関数が用意されていないが、whereTypeを用いたnullの排除ができる

final nonNullList = list.whereType<T>().toList() // 今回は`T=int`

補足

SwiftはcompactMapが用意されている

let list = [1,nil,3,nil,5]
let nonNilList = list.compactMap{ $0 }

KotlinはmapNotNullが用意されている

val list = listOf(1,null,3,null,5)
val nonNilList = list.mapNotNull{ it }
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