Maybe this problem is an exception to the rule (because you're talking about "CSV-like" data, and not just "CSV"), but in general it's a really bad idea to try to roll your own CSV processing with regular expressions. CSV seems very simple, so you tend to think it'll be eaisier to just do it yourself, but there are enough odd little corner-cases that you're almost guaranteed to do something wrong (e.g. do you allow items with commas inside them if they're quoted correctly? if you allow quotes inside of a quoted item, how do you escape the embedded quotes? Is it okay to allow spaces after the commas? If you do, does that break someone else's CSV parsing?).

When last I looked into this, your best bet was to use Text::CSV_XS (or DBD::CSV, which uses it internally), though you need to know that you always want to use the "binary" option (i.e. they got the default wrong).