匹配此字符串没有lookbehind - Javascript正则表达式

Question

We know that JavaScript doesn't support look-behinds. I have been trying to match CC C part of the string. However, it matches C CC C as well.

The regex should match CC or C only.

String is KD IC CC C

Current Regex: (\\s*((CC)|(C)))+

With a look-behind could have been: (\\s*((CC)|((?>=\\s|^)C)))+

What is an alternative here? I have tried non-capturing groups etc. but didn't work.

Because the function with this regex is used many times, I don't have the option to use other JavaScript functions. The only way to achieve it is by using a regex.

I am also using https://www.npmjs.com/package/xregexp of NodeJS. Therefore, I might be able to use its additional functionality. Any help is appreciated.

Answer 1

You can use the word boundary in this case to achieve the match you are looking for.

 var str = 'KD IC CC C'; var found = str.match(/\\bcc?\\b/gi); // or you can use this: /\\bc{1,2}\\b/gi console.log(found); 

Looks like @procrastinator mentioned the same regex in the comments too.