Why is complex data wrapped inside an intermediate type?

为什么要把复杂数据包装在中间类型中呢？

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After the toolbar, you have a simple HTML form wrapped inside an unordered list.

有了工具栏之后，您就有一个封装在无序列表之内的简单HTML表单。

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In RPC style, the XML payload is wrapped inside an operation element in a SOAP body.

在rpc样式中，xml有效负载包装在SOAP主体中的operation元素内。

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Inside lay Roaring Camp's newest citizen, wrapped in a piece of bright red cloth.

VOA: special.2009.06.06

The inside was wrapped with eight inches of insulation and several layers of plastic, he said.

CNN: Inside the bunker: From storm shelter to boy's prison

To paraphrase the words of Winston Churchill, who is seen in newsreel footage of the Potsdam Peace Conference in "The Good German, " Steven Soderbergh's new film is a puzzle wrapped in a mystery inside a perversity.

WSJ: Film Review

"And when I looked at him, he looked back with this scared look and said, 'I can't hold this door shut, ' " said Ms. Brooks, wrapped in a green blanket inside the Moore Community Center.

WSJ: After Oklahoma Tornadoes, Rescue Efforts Focus on Survivors