Day 12 - Panda package manager

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Day 12 - Panda package manager

Perl 6 is not just the language. While without modules it can do more than Perl 5, modules can make life easier. About two years ago neutro was discussed on this blog. I'm not going to talk about it, as it's deprecated today.

Today, the standard way of installing modules is the panda utility. If you're using Rakudo Star, you should have it already installed (try the panda command in console to check it). After running it and waiting a few seconds, you should see help for the panda utility.

$ panda
Usage:
  panda [--notests] [--nodeps] install [<modules> ...] -- Install the specified modules
  panda [--installed] [--verbose] list -- List all available modules
  panda update -- Update the module database
  panda info [<modules> ...] -- Display information about specified modules
  panda search <pattern> -- Search the name/description

As you can see, it doesn't have many options (it's actually similar to RubyGems or cpanminus in its simplicity). You can see the current list of modules at Perl 6 Modules page. Let's say you would want to parse INI file. First, you can find module for it using search command.

$ panda search INI
JSON::Tiny               *          A minimal JSON (de)serializer
Config::INI              *          .ini file parser and writer module for
                                    Perl 6
MiniDBI                  *          a subset of Perl 5 DBI ported to Perl 6
                                    to use while experts build the Real Deal
Class::Utils             0.1.0      Small utilities to help with defining
                                    classes

Config::INI is module you want. Other modules were found because my query wasn't specific enough and found "ini" in other words (minimal, MiniDBI and defining). Config::INI isn't part of Rakudo Star, so you have to install it.

Panda installs modules globally when you have write access to the installation directory, locally otherwise. Because of that you can use panda even when Perl 6 is installed globally without installing modules like local::lib, like you have to in Perl 5.

$ panda install Config::INI
==> Fetching Config::INI
==> Building Config::INI
Compiling lib/Config/INI.pm
Compiling lib/Config/INI/Writer.pm
==> Testing Config::INI
t/00-load.t .... ok
t/01-parser.t .. ok
t/02-writer.t .. ok
All tests successful.
Files=3, Tests=55,  3 wallclock secs ( 0.04 usr  0.00 sys +  2.38 cusr  0.14 csys =  2.56 CPU)
Result: PASS
==> Installing Config::INI
==> Succesfully installed Config::INI

After the module has been installed, you can update it as easily - by installing it. Currently panda cannot automatically upgrade modules, but after a module has been updated (you can watch repositories on GitHub to know when it happens - every module is available on GitHub), you can easily upgrade it by reinstalling the module.

When module was installed, you can check if it works by trying to use it. This is a sample script that can be used to convert INI file into a Perl 6 data structure.

#!/usr/bin/env perl6
use Config::INI;
multi sub MAIN($file) {
    say '# your INI file as seen by Perl 6';
    say Config::INI::parse_file($file).perl;
}