Dave Cross and Modern PERL

At this year's YAPC::EU, we've been having a blast in Granada, Spain, an incredibly beautiful city. The conference has been fun and Dave Cross gave a great lightning talk about Modern PERL (sic). These are devs who are using 5.8, often aren't allowed to use modules, and use CGI.pm for param handling, but print cookies manually. In a similar spirit, I present a subroutine from some client code. It's here with their permission, and it's one of reasons they've hired All Around The World to fix their system. Pay close attention to the sprintf lines.


sub getDate {

       my $DATE = "0";
       # Get the date
       ($day, $month, $year, $hour, $min, $sec) = (localtime)[3, 4, 5, 2, 1, 0];

       # Reformat numbers to have two digits
       $day = sprintf ( "%.2d", $day % 100 );
       $month = sprintf ( "%.2d", ($month++) % 100 );
       $hour = sprintf ( "%.2d", $hour % 100 );
       $min = sprintf ( "%.2d", $min % 100 );
       $sec = sprintf ( "%.2d", $sec % 100 );

       # Fix the year
       $year = $year + 1900;

       # Format the date.
       $DATE = "$day$month$year$hour$min$sec";

       # Return the date
       return $DATE;

I should add that this is some of the nicer code in their system.


I believe it is worth mentioning that the whole function can be replaced by

use POSIX qw(strftime);

sub getDate {
    return strftime '%d%m%Y%H%M%S', localtime;

Why not use strftime() from POSIX?

use POSIX;
print strftime( '%Y%m%d%H%M%S', localtime ), "\n";

BTW, SI standard is year, month, day, hour, minute, second.

I hope there's a video of Dave's talk coming because it sounds like he's seen where I work... Sigh

Though, to be fair, we're using 5.8.8. ;)

This is ... creative. In our code, I usually just find very, very boring if ( $hour < 9 ) stuff. But modulo 100? Too good to call it PERL.

@Ovid: POSIX is a standard module. It comes installed with Perl. For a list of all the standards modules, see perldoc perlmodlib


@shawnhcorey: I'm pretty sure that Ovid knows that POSIX is a standard module :-)

Maybe the author's productivity was judged by LOC/D (Lines Of Code written / Day)?

a nice example. one can see the stumbling around the coder experienced reading perl documentation, trying stuff haphazardly until getting the desired result, never bothering to understand or clean up the failed attempts.

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About Ovid

user-pic Freelance Perl/Testing/Agile consultant and trainer. See http://www.allaroundtheworld.fr/ for our services. If you have a problem with Perl, we will solve it for you. And don't forget to buy my book! http://www.amazon.com/Beginning-Perl-Curtis-Poe/dp/1118013840/