Parsing a CSV file example

#!/usr/bin/perl
use strict;
use warnings;
my @lines = ('12,some text,34',
              '56,"some text, with a comma in",78',
              '99,"some text, with a ""quote"" or two in",100');
for my $i (0..$#lines) {
   my @a = ParseCsv($lines[$i]);
   print "!!start of record\n";
   for my $j (0..$#a) {
     print "$a[$j]\n";
   }
   print "!!end of record\n\n";
}

my @CsvNew = ();
my $CsvField = "";
my $CsvCh = "";
my $CsvState = "";
sub ParseCsv {
   my $text = shift;
   @CsvNew = ();
   $CsvState = "stStart";
   sub endfield {
     push(@CsvNew, $CsvField);
     $CsvField = "";
   }
   sub addchar {
     $CsvField = $CsvField . $CsvCh;
   }
   sub error {
     die("Unexected char ('$CsvCh') in csvState $CsvState");
   }
   for my $i (0..length($text)-1) {
     $CsvCh = substr($text, $i, 1);
     #print "i=$i  csvCh='$CsvCh'  csvState=$CsvState\n";
     if    ($CsvState eq "stStart") {
       if    ($CsvCh eq ',') { endfield();      $CsvState="stStart"      }
       elsif ($CsvCh eq '"') {                  $CsvState="stQuoted"     }
       else                  { addchar($CsvCh); $CsvState="stUnQuoted"   }
     }
     elsif ($CsvState eq "stUnQuoted") {
       if    ($CsvCh eq ',') { endfield();      $CsvState="stStart"      }
       elsif ($CsvCh eq '"') { error();         $CsvState="stQuoted"     }
       else                  { addchar($CsvCh); $CsvState="stUnQuoted"   }
     }
     elsif ($CsvState eq "stQuoted") {
       if    ($CsvCh eq ',') { addchar($CsvCh); $CsvState="stQuoted"     }
       elsif ($CsvCh eq '"') {                  $CsvState="stQuoteQuote" }
       else                  { addchar($CsvCh); $CsvState="stQuoted"     }
     }
     elsif ($CsvState eq "stQuoteQuote") {
       if    ($CsvCh eq ',') { endfield();      $CsvState="stStart"      }
       elsif ($CsvCh eq '"') { addchar($CsvCh); $CsvState="stQuoted"     }
       else                  { error();         $CsvState="stQuoted"     }
     }
   }
   endfield();
   return @CsvNew;
}