Hi,

What i find challenging in perl is the "automagic" that enables a
little code to do a lot. I was looking at a book "Data Munging with
Perl" by David Cross. I've used perl in the past but I forget most of
it after a while and then relearn it when I need to use it again...In
any event (I wish I retained knowledge better) the very first script
in the book would be used on a file like, (assume tab delimited)

band1   song1   aaa     1999
band2   song2   bbb     1966
band3   song3 cccc       1988
band4   song4   dddd  1964
band5   song5   eee       1988

and the given code to get the number of CDs per year is:

my %years;

open FILE, "untitled" or die $!;

while (<FILE>) {
    chomp;
    my $year = (split /\t/)[3];
    $years{$year}++;
}
foreach (sort keys %years) {
    print "In $_, $years{$_} CDs were released.\n";
}

So  "my $year = (split /\t/)[3];" knows that it's input parameter is a
line from <FILE> it doesn't have to told. The [3] obviously says give
me the 4th element in the tab delimited line. The $_ var is well
documented. Again the minimal code approach is challenging for me. And
this can probably condensed even more ?!





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