Regular expressions are convenient for extracting data from strings that have an informal structure, but are not "structured data" (that is, in a format like XML or JSON, for example).

正则表达式用来从有着非正式结构的字符串中提取数据是很方便的，但是对“结构性数据”(就是类似XML，或者JSON那样的格式)则不是。

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What many managers fail to realize is that there is another, complementary, leadership model that exists between the lines in an org chart: the informal structure.

但是，有很多管理人员没能意识到，在企业当中其实还存在着另外一种补充性质的领导模式，那就是非正式的领导。

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Anonymous's informal structure increases the chances that rogue elements can initiate action without widespread support, said Graham Cluley, of security firm Sophos.

BBC: Anonymous denies Westboro attack

In their current form, European corporate states tend to be more informal than their predecessors, drawing on mutually supporting networks of labor, industry and government leaders without the explicit structure of Mussolini's cartels or Roosevelt's code authorities.

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