用正则表达式替换多个字符串

Question

I try to replace some multiple strings with an abbreviation .. . If a string occurrences more than 2 times then it is to replace with string..string . Eg the string is as follows:

var str = 'i,u,br,br,p,p,p,p,br,br,br,br,div,div,div,div,br,br,br,p';
// The result should be as follows:
str = 'i,u,br,br,p..p,br..br,div..div,br..br,p';

Here is my approach, but it doesn't work proper:

str = str.replace(/((,\w+)){3,}/igm, ',$1...$1');

Do you have any idea how can I do it right? Thanks.

Answer 1

Sure:

(\b\w+)(?:,\1){2,}

Demo

What was required is for all the words to be the same, so you have to use a backreference in the pattern.