The problem is that your regex can cause a lot of backtracking. Since (.*?) is also allowed to match a comma, a failed match will mean that each .*? group tries to match a different number of characters. Since you have so many of these groups, there's a huge number of possible matches (all of which will fail), which is why the regex engine takes so much time.

The better approach is of course to use Text::CSV, which will also handle the quoting inside a field for you.

Another efficient but less robust approach is to use split.

Perl 6 - second systems done right

In reply to Re: Is there any regex limitation? by moritz
in thread Is there any regex limitation? by benlaw

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