gistfile1.rb

task :watch_assets => [:compile_css, :compile_js] do |t, args|
  timeout = ENV['WATCH_ASSETS_TIMEOUT'] || '0.2'

  lockdir = './assets.lock'
  cmd = <<-EOS
if mkdir #{lockdir} &>/dev/null; then
  sleep #{timeout}
  rake -s compile_css
  rake -s compile_js
  rmdir #{lockdir}
fi
EOS

  system(%Q{watchmedo shell-command --patterns="*.js;*.scss" --command='#{cmd}' app/views/css/ public/js})
end