字符类减法，从Java语法转换为RegexBuddy [英] Character class subtraction, converting from Java syntax to RegexBuddy

问题描述

Java使用哪个正则表达式引擎?

Which regular expression engine does Java uses?

如果我使用RegexBuddy之类的工具

In a tool like RegexBuddy if I use

[a-z&&[^bc]]

Java中的表达式很好，但是在RegexBuddy中尚未理解.

that expression in Java is good but in RegexBuddy it has not been understood.

实际上它报告:

匹配出现在其中的单个字符 [a-z&&[^bc]

Match a single character present in the list below [a-z&&[^bc]

• a和z之间的字符: a-z
• 字符&[^bc之一: &&[^bc
• 从字面上匹配字符]: ]

• A character in the range between a and z : a-z
• One of the characters &[^bc : &&[^bc
• Match the character ] literally : ]

但我想匹配a和z之间的字符，该字符与不是b或c

but i want to match a character between a and z intersected with a character that is not b or c

推荐答案

像大多数正则表达式一样，

Like most regex flavors, java.util.regex.Pattern has its own specific features with syntax that may not be fully compatible with others; this includes character class union, intersection and subtraction:

• [a-d[m-p]]:a至d，或m至p:[a-dm-p] (联合)
• [a-z&&[def]]:d，e或f (交叉点)
• [a-z&&[^bc]]:a至z，除了b和c:[ad-z] (减法)

• [a-d[m-p]] : a through d, or m through p: [a-dm-p] (union)
• [a-z&&[def]] : d, e, or f (intersection)
• [a-z&&[^bc]] : a through z, except for b and c: [ad-z] (subtraction)

Java正则表达式最重要的"caveat"是matches尝试将模式与整个字符串匹配.这对于大多数引擎而言都是非典型的，有时可能会引起混乱.

The most important "caveat" of Java regex is that matches attempts to match a pattern against the whole string. This is atypical of most engines, and can be a source of confusion at times.

• regular-expressions.info/Flavor比较和减法允许您将Java中的所有辅音"定义为[a-z&&[^aeiou]].

  Subtraction allows you to define for example "all consonants" in Java as [a-z&&[^aeiou]].

  此语法特定于Java.在XML Schema，.NET，JGSoft和RegexBuddy中，它是[a-z-[aeiou]].其他口味可能根本不支持此功能.

  This syntax is specific to Java. In XML Schema, .NET, JGSoft and RegexBuddy, it's [a-z-[aeiou]]. Other flavors may not support this feature at all.

  • regular-expressions.info/XML正则表达式中的字符类
  • MSDN-正则表达式字符类-减法
  • regular-expressions.info/Character Classes in XML Regular Expressions
  • MSDN - Regular Expression Character Classes - Subtraction
  • >字符类背后的意义是什么Java的Regex中有什么交集?

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