读书笔记: 正则表达式30分钟入门教程

正则表达式30分钟入门教程
http://unibetter.com/deerchao/zhengzhe-biaodashi-jiaocheng-se.htm
see also
http://msdn2.microsoft.com/en-us/library/ae5bf541.aspx
中文翻译果然是让我精神恍惚啊^_^


断言: assertion
零宽断言: zero-width assertions

零宽度正预测先行断言
(?=pattern): A subexpression that performs a positive lookahead search
零宽度负预测先行断言
(?!pattern): A subexpression that performs a negative lookahead search
零宽度正回顾后发断言: positive lookbehind
零宽度正回顾后发断言: negative lookbehind

平衡组: Balanced Constructs