I have a text data record that comprises a variable number of 'fields'... and I would like to extract the last field from the record.

Now, I realize I could probably use a (fancy) regex... and I understand they are (often) efficient and so on... but, like a lot of people, I get intimidated by regex... so I was looking for a simpler, array-manipulation method of extracting the last item from a variable length array.

Some example code:

#  $rec = " 2425 S  25  \"   6  47!  86  18  21!  87  23  23!   -     
+  -!   -       -!   96";

use Data::Dumper;

$infile = "2425-pmpk.txt";

open(INFILE, $infile) || die("cant on $infile\n$!\n");
while ($rec = <INFILE>) {
   chomp($rec);
   next unless ($rec =~ /S  25/);
   
   $rec =~ s/^\s+//;  # remove lead/trail spaces
   $rec =~ s/\s+$//;
   
# DOESN'T WORK
   (@junk, $ads) = (split(/\s+/, $rec));

# WORKS OK
#   (@junk) = (split(/\s+/, $rec));
#   $ads = @junk[-1];

# WORKS OK
#   (@junk) = (split(/\s+/, $rec));
#   $idx = $#junk;
#   $ads = $junk[$idx];

# WORKS OK ... BUT AT THE WRONG END OF THE ARRAY
#   ($ads, @junk) = (split(/\s+/, $rec));

print Dumper(@junk);

   printf("$rec\n");
   printf("%d\n", $ads);
}
close(INFILE);

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There are a number of solutions there that I've worked-out... so I've more-or-less come up with a suitable solution... but I guess the primary question is why doesn't the following construct work:

(@junk, $ads) = (split(/\s+/, $rec));

I've looked through the perlfaq, the Camel and Ram books... and have searched through the HallowedHalls(tm) here but couldn't find anything specific..

Would appreciate any thoughts...

In reply to Non-regex Methods of Extracting the Last Field from a Record by ozboomer

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