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javascriptjavaregexsplitregex-lookarounds

JavaScript regex split consecutive string (vs Java)

I have this splitting regex to group consecutive words in String

/(?<=(.))(?!\1)/g

So in Java the above regex would split the string as I'm expected like this

"aaabbbccccdd".split("(?<=(.))(?!\\1)");
// return [aaa, bbb, cccc, dd]

but in JS the same regex will split like this, included my capture group 1

'aaabbbccccdd'.split(/(?<=(.))(?!\1)/g);
/// return ['aaa', 'a', 'bbb', 'b', 'cccc', 'c', 'dd']

So is there anyway to avoid capture group in result in JS (I've tried (?:...) but then I can't use \1 anymore)

And if you have other way or improvement to split consecutive words in JS (using or not using regex), please share it, thank you.

Solution

  • I would keep your current logic but just filter off the even index list elements:

    var input = "aaabbbccccdd";
var matches = input.split(/(?<=(.))(?!\1)/)
                   .filter(function(d, i) { return (i+1) % 2 != 0; });
console.log(matches);