Backreferences can also break down a universal resource indicator into its component parts 反向引用还可以将通用资源指示符( uri )分解为其组件。
Then , you can refer back to them by putting their names in braces in the rules section 然后，您可以在规则部分将其名称放置在大括号内来反向引用它们：
Marks the next character as a special character , a literal , a backreference , or an octal escape 将下一字符标记为特殊字符、文本、反向引用或八进制转义符。
Are unambiguous and cannot be confused with backreferences . backreference behavior is slightly different when the 选项标志被启用时，反向引用行为将稍有不同。
Specifically , when a group makes multiple captures , a backreference refers to the most recent capture 具体地讲，就是当组建立多个捕获时，反向引用引用最近的捕获。
Provides information about how regular expression backreferencing is used to find repeating groups of characters 提供关于如何使用正则表达式反向引用来查找重复字符组的信息。
If a regular expression contains a backreference to an undefined group number , it is considered a parsing error 如果正则表达式包含对未定义的组成员的反向引用，则它被视作分析错误。
If a group has not captured any substring , a backreference to that group is undefined and never matches 如果一个组尚未捕获任何子字符串，则对该组的反向引用是未定义的并且永远不匹配。
A backreference refers to the most recent definition of a group the definition most immediately to the left , when matching left to right 反向引用引用组的最近的定义（当从左到右匹配时，最靠近左侧的定义） 。
One of the simplest , most useful applications of backreferences provides the ability to locate the occurrence of two identical , adjacent words in text 反向引用的最简单的、最有用的应用之一，是提供查找文本中两个相同的相邻单词的匹配项的能力。
