example_package_database.rb

This example demonstrates how to use Mask. It displays all the mask keys for a particular PackageID.

00001 #!/usr/bin/env ruby
00002 # vim: set sw=4 sts=4 et tw=100 :
00003 
00004 =begin description
00005 This example demonstrates how to use Mask. It displays all the
00006 mask keys for a particular PackageID.
00007 =end
00008 
00009 require 'Paludis'
00010 require 'example_command_line'
00011 
00012 include Paludis
00013 
00014 exit_status = 0
00015 
00016 # We start with an Environment, respecting the user's '--environment' choice.
00017 env = EnvironmentMaker.instance.make_from_spec(ExampleCommandLine.instance.environment)
00018 
00019 # Mostly PackageDatabase is used by Environment. But other methods are useful:
00020 if env.package_database.has_repository_named?('gentoo')
00021     repo = env.package_database.fetch_repository('gentoo')
00022     puts "Repository 'gentoo' exists, and has format '" +
00023         (repo.format_key ? repo.format_key.value : '') + "'"
00024 end
00025 
00026 puts "Our favourite repository is '#{env.package_database.favourite_repository}'"
00027 
00028 begin
00029     name = env.package_database.fetch_unique_qualified_package_name('git')
00030     puts "The only package named 'git' is '#{name}'"
00031 rescue NoSuchPackageError
00032     puts "There is no package named 'git'"
00033 rescue AmbiguousPackageNameError
00034     puts "There are several packages named 'git':"
00035     $!.options.each do |o|
00036         puts "    #{o}"
00037     end
00038 end
00039 
00040 exit exit_status
00041