alienfile

Alien::Base was first released in alpha form five years ago this month! The good things that Alien::Base (runtime) and Alien::Base::ModuleBuild (its installer ABMB) did when it was unleashed on the world are many, but chiefly:

  1. It suggested a standard way of providing the compiler and linker flags needed to use an already installed alien. The original manifesto was pretty flip in terms of standards or best practices.
  2. It made it dead simple to create an Alien distribution that “alienized” a package that used autoconf and pkg-config, which probably covers a majority of open source libraries that you would be likely to want to “alienize”. (For those who are unfamiliar, autoconf provides a similar functionality to ExtUtils::MakeMaker in the C world and pkg-config is used to deal with dependencies in the C world).
  3. It made it possible with some work to create an Alien distribution that wrapped around a package that used vanilla Makefile's, CMake, and in some cases crazy custom installers.

So when I was working on:

Git::Database now supports seven different Git backends

A few weeks ago, SROMANOV sent me a patch for Git::Database adding initial support for accessing the Git object database references via Git::Raw. He had already contributed a partial implementation for a Git::Wrapper backend some time ago.

This motivated me to explore that module further, and implement the methods that were missing from Sergey's patch. So I asked JACQUESG to implement a few features that I needed. He was amazingly fast at responding, and I found myself asking for more and more features. And he just kept adding them!

So, thanks to a motivated contributor and a very reactive maintainer, Git::Database 0.08 can now access data from a Git repository using any of these seven Perl Git backends:

There are in fact more Git backends on CPAN... Anyone interested in adding support for Git::Class must have understood by now that patches are welcome. :-)

Choosing a Log Level

Like all subjective decisions in technology, which log level to use is the cause of much angry debate. Worse, different logging systems use different levels: Log4j has 6 severity levels, and Syslog has 8 severity levels. While both lists of log levels come with guidance as to which level to use when, there's still enough ambiguity to cause confusion.

When choosing a log level, it's important to know how visible you want the message to be, how big of a problem it is, and what you want the user to do about it. With that in mind, this is the decision tree I follow when choosing a log level:

Perl 5 Porters Mailing List Summary: March 22nd-27th

Hey everyone,

Following is the p5p (Perl 5 Porters) mailing list summary for the past week.

Enjoy!

Using the Perl debugger with DBIx::Class

I wrote about using the Perl debugger with Moose. In that post, I showed how to use DB::Skip to make it easier to use the Perl debugger with Moose and other modules whose guts you don't want to wade through.

Today's debugger hack will make using the debugger with DBIx::Class much easier.

That Darn Single Quote

The more I think about the “single-quote as alternate package separator” thing I mentioned in my last post, the more it bothers me. The problem I ran into, trying to print "$user's crontab is missing!\n", generated an “uninitialized value” warning. It did NOT get picked up by strict mode—which was on—because packaged-qualified variables are always OK.

This strikes me as a source of hard-to-find and relatively easy-to-generate bugs. Given all the other stuff that has been deprecated out of Perl over the years, I am surprised this hasn’t been tagged for deprecation. Especially given that, according to a comment from preaction, the single-quote as a package separator was considered archaic as of Perl 5.6.

Saving your test suite history

If you saw my FOSDEM talk about Building a Universe in Perl, I show some examples of the code we use to model behaviors in our universe. I start talking about out test suite at one point and that's probably the most exciting part. You see, we've been fixing our leaderboard system in part because I can do this:

That's a truncated version of our test failure report for tests failing on master. Leaderboard tests show up twice in there.

Ever have an failing test and trying to remember if it failed before? Is it fragile code? Is it fragile tests? Has it ever failed on your master branch? What percentage of your tests fail? Well, now you can find out.

Something New Every Day

Just now, while attempting to do

print "$user's crontab is missing!\n"

I got the error “Use of uninitialized value in concatenation (.) or string…”, and after a bit of testing, I discovered that “$package'varname” is apparently an alias of “$package::varname” (in my case, Perl was trying—and failing—to print $user::s).

Did everyone else know this? This is literally the first time I have run across this in almost 20 years of Perl programming

(Of course a quick Google search turns this up in the opening paragraphs of the perlmod docs—I wonder if it’s time to read all of that stuff cover-to-cover?)

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