Here's an answer from Mastering Regular Expressions:

sub parse_csv {
  my $text = shift; ## record containing comma-separated values
  my @new = ();
  push(@new, $+) while $text =~ m{
    ## the first part groups the phrase inside the quotes
    "([^\"\\]*(?:\\.[^\"\\]*)*)",?
      | ([^,]+),?
      | ,
    }gx;
    push(@new, undef) if substr($text, -1,1) eq ',';
    return @new; ## list of values that were comma-spearated
}
## Use like this: @goodlist = parse_csv($csvlist);
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Ugly, to be sure, but the complexity level really kicks up a notch when you add the delimiters into the fields themselves. Also, the above snippet allows quotes inside the fields, as long as they are backslashed.