List::Slice - Slice operations for lists

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How many times have you needed to do this?

my @found_names = grep { /^[A-D]/ } @all_names;
my @topfive = @found_names[0..4];

Or worse, this.

my @topfive = ( grep { /^[A-D]/ } @all_names )[0..4];

There's got to be a better way

Or this.

my @bottomfive = @names < 5 ? @names : @names[$#names-5..$#names];

Or this.

my @names
        = map { $_->[0] }
        sort { $a->[1] <=> $b->[1] }
        grep { $_->[1] > $now }
        map { [ $_->{name}, parse_date( $_->{birthday} ) ] }
        @all_users;
my @topfive = @names[0..4];

There's got to be a better way!

There's got to be a better way

Now there is! Introducing: List::Slice!

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Announcing Statocles

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Static site generators are popular these days. For small sites, the ability to quickly author content using simple tools is key. The ability to use lower-cost (even free) hosting, often without any dynamic capabilities, is good for trying to maintain a budget. For larger sites, the ability to serve content quickly and cheaply is beneficial, and since most pages are read far more often than they are written, generating a full web page to store on the filesystem can improve performance (and lower costs).

For me, I like the convenience of using Github Pages to host project-oriented websites. The project itself is already on Github, so why not keep the website closely tied to it so it doesn't get out-of-date? For an organization like the Chicago Perl Mongers, Github can even host custom domains, allowing easy collaboration on websites.

It's through the Chicago.PM website that I was introduced to Octopress, a blogging engine built on Jekyll. It's through using Octopress that I decided to write my own static site generator, Statocles.

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Managing SQL Data with Yertl

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Originally posted on blogs.perl.org -- Managing SQL Data with Yertl

Every week, I work with about a dozen SQL databases. Some are Sybase, some MySQL, some SQLite. Some have different versions in dev, staging, and production. All of them need data extracted, transformed, and loaded.

DBI is the clear choice for dealing with SQL databases in Perl, but there are a dozen lines of Perl code in between me and the operation that I want. Sure, I've got modules and web applications and ad-hoc commands and scripts that perform certain individual tasks on my databases, but sometimes those things don't quite do what I need right now, and I just want something that will let me execute whatever SQL I can come up with.

Yertl (ETL::Yertl) is a shell-based ETL framework. It's under development (as is all software), but included already is a small utility called ysql to make dealing with SQL databases easy.

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Manage Boilerplate with Import::Base

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Originally posted as: Manage Boilerplate with Import::Base on blogs.perl.org.

Boilerplate is everything I hate about programming:

  • Doing the same thing more than once
  • Leaving clutter in every file
  • Making it harder to change things in the future
  • Eventually blindly copying without understanding (cargo-cult programming)

In an effort to reduce some of my boilerplate, I wrote Import::Base, a module to collect and import useful bundles of modules, removing the need for long lists of use ... lines everywhere.

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