code>フィールドから値をクローンしなければなりませんでした。</p>
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ここも節冒頭と同様。やはり強すぎるか？
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With our new knowledge about iterators, we can change the `new` function to
take ownership of an iterator as its argument instead of borrowing a slice.
We’ll use the iterator functionality instead of the code that checks the length
of the slice and indexes into specific locations. This will clarify what the
`Config::new` function is doing becaus