Thank You, Coveralls.io

For letting me know my test coverage has increased by 0.00006%.

Coveralls.io screenshot

(Seriously it's a pretty cool service though.)

Finding Squares in Matrices

I don't usually take part in the Perl Weekly Challenge but one of this week's challenges caught my eye. I thought it could be a fun thing to attempt and decided to use Zydeco to help solve it.

The problem is that you're given a matrix of 0s and 1s:

You need to find any squares (equal length sides) where all four corners are 1s:

Applying Operators to Coderefs

In algebra, there's this pretty funky concept:

(f+g)(x) = f(x) + g(x)

And I was thinking if $f and $g were coderefs, what could $f + $g be?

Zydeco::Lite

Today I released Zydeco::Lite, a re-implementation of Zydeco but just using standard Perl syntax. So for example, class { ... } becomes class(sub { ...});.

This has the advantage of much faster compile time, similar run time speed, fewer dependencies, and compatibility with older versions of Perl before the keyword API was introduced. Of course, in some circumstances these aren't important concerns, so the nicer syntax of the full Zydeco will be preferred.

Zydeco and Zydeco::Lite are both based on MooX::Press which itself is based on Moo, Type::Tiny, and other modules. I've taken the synopsis example from the Zydeco documentation and rewritten it using the different layers of abstraction.

Web Scraping with Zydeco

So I like to keep local copies of my blogs.perl.org blog posts as Atom entries, but noticed yesterday that I had a few gaps in my collection. The Atom feeds offered by blogs.perl.org only have the most recent articles though, so I decided to write a quick script to scrape the posts. Luckily, I managed to get a table containing the URLs for each post I needed, so I didn't need to bother with following links to find the pages; I just needed to grab the content from them.

I thought some people might find the code interesting especially for its use of lazy attributes. This is one of those "it only needs to be used once, so making the code maintainable isn't important" kinds of projects, do bear that in mind. I've cleaned up the whitespace and added comments for this blog post, but other than that, it's just a quickly hacked together script.

About Toby Inkster

user-pic I'm tobyink on CPAN, IRC and PerlMonks.