Rakefile in pione-0.1.0 vs Rakefile in pione-0.1.1

@@ -1,16 +1,16 @@
 require "bundler/gem_tasks"
 
 $stand_alone = "bin/pione-client --stand-aline"
 
 desc 'generate HTML API documentation'
-task :html do
-  sh "yard doc -o html --hide-void-return --no-api --private"
+task 'html' do
+  sh 'bundle exec yard doc -o html --hide-void-return --no-api --private'
 end
 
 desc 'Show undocumented function list'
 task 'html:undoc' do
-  sh 'yard stats --list-undoc --no-api --private'
+  sh 'bundle exec yard stats --list-undoc --no-api --private'
 end
 
 desc 'count characters in input direcotry'
 task 'example:CountChar' do
   sh "ruby -I lib %s -i %s %s" % [