def install_gem name, version = nil, rdoc = true
should_not_sudo = Hoe::WINDOZE || ENV["NOSUDO"] || File.writable?(Gem.dir)
null_dev = Hoe::WINDOZE ? "> NUL 2>&1" : "> /dev/null 2>&1"
gem_cmd = Gem.default_exec_format % "gem"
sudo = "sudo " unless should_not_sudo
local = "--local" unless version
version = "--version '#{version}'" if version
cmd = "#{sudo}#{gem_cmd} install #{local} #{name} #{version}"
cmd += " --no-rdoc --no-ri" unless rdoc
cmd += " #{null_dev}" unless Rake.application.options.trace
puts cmd if Rake.application.options.trace
system cmd
end