See http://jquelin.blogspot.com/2010/02/ironman-challenge-status.html and http://www.lowlevelmanager.com/2010/01/perl-iron-man-challenge-is-cron-still.html

wtf?

See also:

1. WTFish side of using Perl talk at YAPC::EU 2009 – slides
2. YAPC::EU 2010 Pisa – my presentation
3. More on foreach localisation

After the conference attendees are encouraged to express their opinions on presentations they attended and grade them. Then the aggregated grades and opinions are sent to speaker.

I was a bit nervous, but fortunately presentation about WTFish side of using Perl was graded between 7 and 10 (on a scale from 1 to 10), mostly 8-9.

There were also opinions – good and bad.

Bad: I could have been speaking louder and with better intonation and gestures. Slides also could be a bit better. Someone even wrote “Poor guy, it is hard to present in another language. I hope he isnt disheartened, his presentation is good”

Good opinions (quoted from the feedback I got):

• Covered well some common but not obvious traps in Perl for newbies. The material was good.
• Good title and subject – humourous way to present this sid of Perl. As a total beginner some parts I knew of and felt the same WTFness and it is nice to feel that it is as mad as I thought!
• This presentation pin pointed some of the things that regularly “bite” newbies, so it was most valuable. It had many examples, and I hope I can remember them all. [ note: there are slides available to download at this blog, so you don't have to remeber all   - Lech ]

Poor guy, it is hard to present in another language.	I hope he isnt
  disheartened, his presentation is good

Thanks for good opinions and also for bad – those taught me something about presentations. Next time it will be better

See also:

1. WTFish side of using Perl talk at YAPC::EU 2009 – slides
2. YAPC::EU 2010 Pisa – my presentation
3. YAPC::EU 2009 in Lisboa (Lisbon, Lizbona)!

Nice:

• bug-fixes, optimisations, tuning. Runs faster.
• autodie pragma

Strange:

• “..” operator is interpretedin boolean context when used inside a when statement – yet another WTF. So, the behaviour of “..” is not less consistent. On the other hand it may be usefull.
• Change of smart match behavior in comaprison to 5.10
1. better encapsulation
2. ordering matters – $key ~~ %hash is OK, while %hash ~~ $key is not.
3. distributive – applies itself recursively across data structures.  Isn’t it getting too smart? And too complex to understand in real code? And too WTFish? I’ll quote the fragment of perl tips newsletter from http://perltraining.com.au/
   

   following expression is *true* when evaluated under 5.10.1, but *false*
   under 5.10.0:

   ‘bar’ ~~ [ 'foo', [ 'bar', 'baz' ], ‘qux’ ]

   In the same vein, given the following code:

   [ 'foo', 'bar', 'baz' ] ~~ \&subroutine

   Perl 5.10.1 will call the subroutine *three* times (once for each
   element), and the whole expression will be considered true if *all* the
   results are true. On the other hand, Perl 5.10.0 would call the
   subroutine only once, passing in the whole data structure.

See also:

1. More on foreach localisation
2. Utf8 in web perl application (LAMP) – part 2 – Encode
3. Utf8 in web perl application (LAMP)

How to have nice colours in spreadsheets: use set_custom_color($index, $red, $green, $blue)

For example:

my $light_orange = $workbook->set_custom_color(43, 255, 226, 171);
my $ligth_yellow = $workbook->set_custom_color(42, 255, 255, 204);
my $light_purple = $workbook->set_custom_color(40, 225, 204, 255);

See also:

1. Unicode horror – nice tool to convert
2. Nice people I met at YAPC::EU
3. Nice people I met at YAPC::EU – continued

Then, my wife asked me another question – ok, if it is so great, why do so few people and companies write in it?

This was question I couldn’t find answer for. I told her about that is not so easy to make .exe file from perl script, but as I heard strawberry perl is good in doing it. Or PAR. I’ll have to look closely at them both in near future. Anyway, in C/C++ it is the most natural way to run the program – to make executable of it In Perl it is not the natural way. And some companies prefer to have executable files, for example to sell them

Anyway, that is good question: Why Perl is not so popular as C-something, or java?

See also:

1. Perl as good as java, python and PHP way above
2. Perl WTFs – last in function
3. Perl 5.10.1

To install this,  head to http://adserver.szabgab.com/

Gabor is also a developer of padre – perl IDE.

Thanks Gabor!

See also:

1. Perl ads here
2. Nice people I met at YAPC::EU – continued
3. installing from CPAN without root

Recently I was wondering about pros and cons of working as Perl developer in two ways:

1) In office, in a big company

2) by telecommuting or other way working in other place that the employer is

They have both advantages and disadvantages.

In office, advantages are: nice colleagues (I am lucky to have them now), free coffe and tea and milk and sugar and…, constant daily routine, a bit of fun/laughing/relax everyday (face it, noone works 100% of the time – it would be also bad for their creativity, physical and mental health etc – for example we are advise to stop looking at minitor every hour for about 5 minutes), fixed hours with some flexibility. Disadvantages: daily commute, trafic jams, earnings based on world region/country, even city.

Telecommute: higher earnings, possiblity to geoarbitrage (I mean earning in one country, living in another – cheaper, or even constantly travel – for more ideas on this see: 4HWW ), no commute, no traffic jams. Disadvantages: I assume you are paid on results – so if you screw up, you have free work overtime. No colleagues, no free coffe nor tea. Your home is your work – that is not good. Unless you rent some office space or use shared working place. Hard to say more, I never worked like this.

What do you think?

See also:

1. Perl WTFs – last in function
2. Website authorization – my solution
3. Utf8 in web perl application (LAMP) – dbi, mysql

One day I was using global var in script (lame, I know). I wanted to use it in foreach. And its value magically disappeared when called other subroutine. This was strange.

This was a script to make reports for customers. The code looked like this (many parts taken out for brevity and to protect the innocent ) :


#!/usr/bin/perl
use strict;
use warnings;
my $custid; # to store customerid.
my %rep_conf;
$rep_conf{'Something-GmBH'}{'custid'}=12345;
(...more config data kept in that hash...)
my $cust_name; # customer name
foreach $cust_name (keys %rep_conf) { # in that hash we get report configuration. The key was customer name.
print("$cust_name"); # here is still exists
$custid = $rep_conf{$cust_name}{'custid'}; # customer id was taken from config hash
$firstsheet = &get_sheet; # get data for our report
(...)
sub get_sheet {
print($custid); # works
print($cust_name); # empty. WTF?
(...)


I scratched my head – why the $custid value exists and $cust_name value disappeared?

I had I hunch to read about foreach in perl docs:

The foreach loop iterates over a normal list value and sets the variable VAR to be each element of the list in turn. If the variable is preceded with the keyword my, then it is lexically scoped, and is therefore visible only within the loop.

Sounds rational. But it was no “my” there:
foreach $cust_name (keys %rep_conf)

Otherwise, the variable is implicitly local to the loop and regains its former value upon exiting the loop.
If the variable was previously declared with my, it uses that variable instead of the global one, but it’s still localized to the loop. This implicit localisation occurs only in a foreach loop.

Here is the mystery solved.  Strange indeed – only for/foreach loop behaves like this.

See also:

1. Perl 5.10.1
2. Perl WTFs – last in function
3. Utf8 in web perl application (LAMP) – part 2 – Encode

And, more important for myself – what should I do?

There are several things:

• spread the word that perl is great and not dead, by for example joining ironman blogging chalenge
• wait, and do nothing – if perl is good then it may defend itself without my help
• learn a new language, to be safe. Or brush up old good java or C-something.

What do YOU think about it?

See also:

1. Perl – why not popular
2. Working as perl developer – telecommuting
3. WTFish side of using Perl talk at YAPC::EU 2009 – slides

• http://perl.baczynski.com/lisboa/WTF.odt
• http://perl.baczynski.com/lisboa/WTF.pdf

Feedback about my talk is appreciated, use comment field below

See also:

1. My presentation at YAPC::EU::2009 was graded
2. YAPC::EU 2009 in Lisboa (Lisbon, Lizbona)!
3. Nice people I met at YAPC::EU