The solved problem that isn't, is

In the title of an excellent blog post, Laurence Tratt calls parsing, "the solved problem that isn't". I thought this phrase captured the current situation in parsing theory and practice very nicely. In stating that parsing is not a solved problem, Tratt realized he was taking on a consensus. But the consensus is fading -- for example, neither side in the interchange between Might/Darais and Russ Cox expresses complete contentment with the state of the art.

CPAN Testers Summary - July 2012 - Head On The Door

July was a relatively quiet month for CPAN Testers. Although reports have been flowing, our attentions have largely been elsewhere. Development work behind the scenes is still continuing, but nothing major to report just yet.

Ben Bullock asked on the mailing list, whether he could search other people's test reports? The problem currently with this, is that we don't really expose the reports themselves, except via the CPAN Testers Reports website, when you specifically ask for the report. The reasons for this have largely been because the search of the Metabase still needs to be written. The demand on the current Metabase is expensive, and until we are able to move to the new backend system, we can't afford to expose the results. For the time being the Analysis site covers some of the demands, but Ben's specific needs aren't covered.

Location, Location, Location

By way of explanation...

In preparing this and my previous blogs, I have noticed aspects where Devel::Trepan could be improved. For this blog, I discovered when comparing Devel::Trepan output with that from a recent perl5db that perl5db sometimes prints several lines of output to try to show a full Perl statement. Devel::Trepan prints a single line — normal in command-line debuggers. However, do see the set auto list command.

As I've done in preparing previous blogs, I then take time from writing the blog to improve Devel::Trepan. Although no one has said anything about this yet in prior blogs, the output you see in the blogs may be a little bit different than what you see if you install from CPAN. However it does match what you will see if you install from the github repository.

But this brings up a couple of other points. First, that one of the reasons that perl5db is probably hard to replace by any debugger is that right now people are still tweaking it.

Back in London

Life can be strange. Not counting endless transits through Heathrow (presumably some horrid form of karmic justice for a particular wicked former life), I have visited London only twice in the past decade. And offered not a single public class there in all that time.

Yet now I'm lining up for my second London visit, and second series of public classes, in six months. And the first person I have to thank for that is the same person who took care of me in London on my very first visit, over ten years ago now: the inimitable Dave Cross. It was Dave who put me in touch with the wonderful folks at FlossUK, who are bringing me back in October for a second installment of Presentation Aikido, as well as offering my Understanding Perl Regexes class.

A Method::Signatures Retrospective

As some of you may know, I worked on a partial rewrite of Method::Signatures last year, mainly to add Moose types to the sigs, but also to do some tweaks here and there, and to use it as a base for Method::Signatures::Modifiers (included with MS), which can replace MooseX::Method::Signatures inside MooseX::Declare.  This latter reason was the primary goal for me, and I’ve gleefully been using MS, and MSM, in practically all the code I’ve written since.  I’ve also ported over a rather large codebase (although admittedly not much of it was using MXD).  We’re almost at the eleven month mark since our first release of the new MS, so I thought it might be interesting to check in with how things are doing.

The Conference T-Shirts

The T-Shirts have finally arrived. Weirdly, some of them are longsleeved, which we didn't order. But there's no time to send them back. Maybe you can wear them in winter.


We chose to go for two colors for attendees this year, blue and grey. I hope you like them. The bright yellow ones are for the organizers, so they stick out.

DC PM Podcast Moved

Hi All,

The DC PM Podcast has changed hosts. This was due to multiple reasons, but the podcast will reside at the new address for the foreseeable future. The new location is

Also, the underlying podcast code is now open source! It’s available at


Not to Hot for Mojo

I saw a post out in the Blogosphere today about getting weather info from NOAA (The United States National Weather Service). Oh! the horrors of using XML::LibXML or XML::DOM or those other hairy XML modules to get at the data.

The blogger didn't seem to keen on my quick and dirty Mojolicious solution:

$ perl -Mojo -E 'say g("")->dom("temp_f")->first->text'

I guess I was a bit too brief and off the point, so here's a nicer example:

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