diff options
author | shyouhei <shyouhei@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2007-08-22 01:53:51 +0000 |
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committer | shyouhei <shyouhei@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2007-08-22 01:53:51 +0000 |
commit | 1e760c0be3ed35874204114e7454509f740c0fe2 (patch) | |
tree | a75eb2b1eea073830902d1fa49c568c4525c8b57 /ruby_1_8_6/lib/test/unit/util/observable.rb | |
parent | a2055d63b41a6678dc7aeb17d0bece314e700c5a (diff) |
add tag v1_8_6_71v1_8_5_71
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/tags/v1_8_5_71@13189 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'ruby_1_8_6/lib/test/unit/util/observable.rb')
-rw-r--r-- | ruby_1_8_6/lib/test/unit/util/observable.rb | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/ruby_1_8_6/lib/test/unit/util/observable.rb b/ruby_1_8_6/lib/test/unit/util/observable.rb new file mode 100644 index 0000000000..3567d34271 --- /dev/null +++ b/ruby_1_8_6/lib/test/unit/util/observable.rb @@ -0,0 +1,90 @@ +#-- +# +# Author:: Nathaniel Talbott. +# Copyright:: Copyright (c) 2000-2002 Nathaniel Talbott. All rights reserved. +# License:: Ruby license. + +require 'test/unit/util/procwrapper' + +module Test + module Unit + module Util + + # This is a utility class that allows anything mixing + # it in to notify a set of listeners about interesting + # events. + module Observable + # We use this for defaults since nil might mean something + NOTHING = "NOTHING/#{__id__}" + + # Adds the passed proc as a listener on the + # channel indicated by channel_name. listener_key + # is used to remove the listener later; if none is + # specified, the proc itself is used. + # + # Whatever is used as the listener_key is + # returned, making it very easy to use the proc + # itself as the listener_key: + # + # listener = add_listener("Channel") { ... } + # remove_listener("Channel", listener) + def add_listener(channel_name, listener_key=NOTHING, &listener) # :yields: value + unless(block_given?) + raise ArgumentError.new("No callback was passed as a listener") + end + + key = listener_key + if (listener_key == NOTHING) + listener_key = listener + key = ProcWrapper.new(listener) + end + + channels[channel_name] ||= {} + channels[channel_name][key] = listener + return listener_key + end + + # Removes the listener indicated by listener_key + # from the channel indicated by + # channel_name. Returns the registered proc, or + # nil if none was found. + def remove_listener(channel_name, listener_key) + channel = channels[channel_name] + return nil unless (channel) + key = listener_key + if (listener_key.instance_of?(Proc)) + key = ProcWrapper.new(listener_key) + end + if (channel.has_key?(key)) + return channel.delete(key) + end + return nil + end + + # Calls all the procs registered on the channel + # indicated by channel_name. If value is + # specified, it is passed in to the procs, + # otherwise they are called with no arguments. + # + #-- + # + # Perhaps this should be private? Would it ever + # make sense for an external class to call this + # method directly? + def notify_listeners(channel_name, *arguments) + channel = channels[channel_name] + return 0 unless (channel) + listeners = channel.values + listeners.each { |listener| listener.call(*arguments) } + return listeners.size + end + + private + def channels + @channels ||= {} + return @channels + end + end + end + end +end |