I need to split a string by commas, but excluding any commas between parethesis

Here's a start, which doesn't use lookahead assertions. It works on your tests case, but I would throw more tests cases at it before putting it into production. 

local $_ = "this, that, those, these (not enough, nope, never), there"
+;

while ( /(?:^|, )([^,]+\(.*?\)|[^,]+)/g ) {
    print $1, "\n";
}

[download]
You have to understand a bit about backtracking to get how this works. It proceeds by trying to match, in this order
  1. at the beginning of a string, a word followed by a parenthetical
  2. at the beginning of a string, a word
  3. following ", ", a word followed by a parenthetical
  4. following ", ", a word

In reply to Re: Splitting a comma-delimited string where a substring could countain commas by dws
in thread Splitting a comma-delimited string where a substring could contain commas by Eisbar

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