Using single brackets () versus double brackets ([]) is a personal preference and really depends on how you've been taught commands and shell scripting.

使用单层方括号()还是双层方括号([])是个人习惯问题，实际上取决于您如何学习命令和shell脚本编程。

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A stereotype allows you to attach a new meaning to a UMl foundation class, such as class, and it is represented on a UMl diagram as a name surrounded by double brackets .

构造型允许您为uml基础类(如Class)附加新的意义，构造型在uml图上表示为一个由双尖括号括起来的名称。

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However, a slash or a double slash ( / or // ) at the front of a predicate in square brackets does not have a context and therefore refers to the root of the document.

但是，方括号中谓词前的单斜线或双斜线（/ 或 //）没有上下文，所以引用到文档的根。

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