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In my last D&D post I had at least the first problems worked out for Character race. Now I think I will move into the most challenging of all the 'Class' of a character.

In D&D a 'Class' is the role (JOB) a character plays in the game ie fighter, thief, mage etc. There are 5 primary Classes and 5 sub classes which is easy enough to model with Moose a 'Role' for each of the 10 and we are done.

Unlike the epic adventures above a character's 'Class' is not that easy to nail down. The rules around class are a mix subtle complexities, there may be only 5 basic 'Character' 'Classes' for 'Players' and 'NPCs' but each Character falls into one of these types

• NPC with no class ie (0 level human farmer, Halfling barkeep, etc)
• NPC or Player with a single class (Fighter, MU, Cleric)
• NPC or Player with multi-classes (Fighter/MU, Cleric/Assassin)
• NPC or Player with two Classes (Fighter-MU, Cleric-Fighter)

In a recent post, Chris K asks, why do I recommend using function() rather than &function() or &function. I happened to see it right before heading to bed, but I wanted to respond, so who knows if this is a good example or not. Anyway here goes, look at this code (seen below if you have javascript), it prints 6 lines, do you know what they will be?

Hello everyone.

In trying to find places that I might be able to exchange links to get traffic to my tutorial site, I found an article about how one should determine if a tutorial is good. One of the things that they mention is that a tutorial that teaches

&subname()

as a valid subroutine calling convention is out of date. It continues to explain that this does do something, but not what people think it does.

As a matter of fact, I just finished writing a major tutorial on subroutines myself last night. I have looked at numerous resources, all of which say

&subname;

(I know that's slightly different, but similar enough to cause alarm) and

subname ()

are both acceptable. I looked again today, and found the same information. So could someone please clear this up...what (if any) difference is there between these two conventions, and am I making some major mistake if I write tutorials with the ampersand method?

I'm relatively pleased with my work in creating parallel testing with Test::Class::Moose, but I wanted to make sure that it worked with a real world example, so today I took a small, but real test suite and converted it and tried out my parallel testing code. The results were interesting.

In the continuing story of Moose and D&D I left off with what I think was a slick use of Moose:Util to load in a Character's race.

As all long term D&D players now you will eventually run into a player who says the following;

Well in my present 'Character' class I allow this as my race is just a string.

  has 'race' =>(
	is		=>'ro',
	isa		=>'Str',
);

So this post will look into how to handle this sort of sin against nature.

In the old days it was simple, each race was a class and if you tried something like this

One of the things developers often struggle with is dependency resolution.

For example:

cpanm WWW::Curl::Easy -v

.....

Configuring WWW-Curl-4.15 ... Locating required external dependency bin:curl-config... missing.

Unresolvable missing external dependency.

Please install 'curl-config' seperately and try again.

NA: Unable to build distribution on this platform.

The purpose of Alien modules is to provide external libraries or other dependencies for CPAN packages. This Alien2 Manifesto updates the original Alien module description based on practical lessons from existing Alien module implementations and some perceived limitations.

The original Alien manifesto provided the idea but not a framework for how modules in the Alien namespace were to work. The plan was to "let evolution work for us and see what individual Alien packages need and then eventually factor it out". We are now more than 10 years after this first proposal and there are now some lessons to be learned from current implementations of Alien modules. Let's start with a review of the responsibilities of an Alien module and some observations.

On installation, make sure the required package is there, otherwise install it.

This is the main purpose of Alien modules, to provided external library or program dependencies needed for CPAN modules installation and operation.

This is part 4 of an ongoing series where I explore my relationship with Perl.  You may wish to begin at the beginning.

This week we look at code legibility.

Last week I talked about why Moose is important to my journey as a Perl programmer, and where I feel that it could be even better.  I concluded that it all comes back to code legibility. 

In my last post I again ending up like poor Keith Haring in his picture below.

I programmed what I wanted but it was beginning to look like the same stuff I started with.

So playing around a bit I remembered that Moose has the before, after and around Method Modifiers that work like DBI's callbacks that some of you might remember form one of my earlier posts. The great thing about these is that can be used from inside a role for code outside the role as long as the code is referenced in a 'requires'.

So I to move the max values out of the Character class and into the Dwarf role I gave this a shot

I have translated "Perl Reverse Dictionary/Array".

Perl Reverse Dictionary/Array

A few months ago I released Graphics::Potrace, that provides Perl bindings to the potrace library. So, if you want to convert rasters into vectors from Perl... you know where to go.

You'll want to checkout the forks branch to see it in action. Read the docs for Test::Class::Moose::Role::Parallel to see how to use it (you'll probably need to create your own schedule).

What follows is a very naïve benchmark where I reduced a 12 minute test suite down to 30 seconds.

With my last post I managed to apply a role to an instance of a class. What I think this will allow me to do is keep my base 'classes' from sprawling out of control while also encapsulation a good number of Game Rules' (or Biz Rules) in to small parts that I can easily reuse.

So far it has handled things quite well and even taught me a few things and I think has really exposed what Roles can do in Moose. Now as my D&D story moves along I am about to jump into what I think is going to be the to big test for Moose.

Character Races??

The differing races bring a new level of complexity to the game, well except mundane old humans who, unlike the other races, get no extra abilities, bonuses, penalties or alike.

JAGC is a server for code golf, where users write the shortest code using all standard features of scripting languages for solve tasks.
Users can add new tasks with unit tests, invent solutions and submit them.
JAGC will run tests for these solutions to determine the winner.

We will be glad to see your feedback.

Visit about page for more information.

Pinto is an application for creating and managing a custom CPAN-like repository of Perl modules. Pjam is a tool which enables automatic creation of perl applications distribution archives from source code using pinto. Pjam enables continues integration in PERL. Right now pjam fits only Module:Build based projects ( Build.PL should be provided ) kept under subversion SCM, but I may change this if interest will be shown.

Pjam can be used in two ways - as command line utility and via web api to take some actions remotely.

Checkout https://github.com/melezhik/jam for detailed info.

Imagine you open up a test file and you see the following:

is foobar(3), 17, 'foobar(3) should return 17';
is foobar(2), 15, 'foobar(2) should return 15';
is foobar(3), 17, 'foobar(3) should return 17';   # duplicate?
is foobar(4), 20, 'foobar(4) should return 20';
is foobar(3), 17, 'foobar(3) should return 17';   # duplicate?

Well, that looks strange and duplicated tests are a code smell. However, it could be a code smell in one of two ways. It's probably the case that some programmer got sloppy and duplicated the tests so do you delete the extra tests?

In my last D&D post I managed to get my generic 'OpenDoorsOnA' role working with my 'Fighter' class but I was left wondering if I would make better sense to make 'Exceptional' Strength a role then only use it the rare time that a 'Fighter' character has 18 strength????

Whenever I see the phrase 'conditionally loads the needed class' in the spec documentation it sends shivers down my spine. Then again anyone who as used DBI has used conditional loading of classes but most times I see silly shortcuts like this

There's a common programming challenge where you write a program to take a dollar amount from the user, and then return the simplest way to create that amount with only coins (using the fewest coins possible). I took a crack at this a while back, and I would like to know if there are ways it could be improved or if you would have done it differently.

The section on reserved names in GCC documentation gives several recommendations that probably the vast majority of C programs in the world do not follow.

Nevertheless, these are all good practices, and an interesting exercice was to check how the latest stable perl source code behaves v.s. these recommendations. As of the day writing this blog entry, this is perl-5.18.1.

The analysis has been done using c2ast.pl tool, from MarpaX::Languages::C::AST package, a Marpa::R2 powered C parser, advertised previously in this blogs.perl.org entry by Jeffrey Kegler.

Detailed list of "violations" is at this gist, generated on linux and gcc version 4.8.2 (Debian 4.8.2-10). It is interesting to note that over 1316 hits, there are 8 categories, with 4 of them eating 98% of the hits:

Here is one way

 
      perl -nE '
            /=head2.*L<([^|]+)/ and $s{$1}++;
           END{ say for (keys %s)}' `perldoc -l perllocal` | 
      while read f; do cpanm $f; done

What are some others?