 gulp.task 'default', [ 'build' ]
 
 # PARAMS:
-# --bundle: true/false, default to false
-# --cdn: 'polygit'/'azure'/'wcdn', default to undefined
-# --lint: true/false, default to false
+# --bundle: true/false(nonexistent), default to false
+# --cdn: false(nonexistent)/'polygit'/'azure'/'wcdn', default to undefined
+# --lint: true/false(nonexistent), default to false
 
 options =
   bundle: argv.bundle || false
-  cdn: argv.cdn
+  cdn: argv.cdn || false
   lint: argv.lint || false
 
 console.log options

  # TODO currently not that flexible and robust with string replacing
  # TODO currently lib version via CDN is hardcoded

  unless options.cdn?
    return runSequence('noop', cb)

  # 1. index: external libs like lodash, polyfills in index -> jsdelivr

  src = []

  # clean up bundled app internal scripts, styles, aurora_components
  if options.bundle is true
    src = src
      .concat paths.elements.internal.folderToCleanup
      .concat paths.app.internal.styles.folderToCleanup
      .concat paths.app.internal.scripts.folderToCleanup

  # clean up bower dependencies, if they've been bundled, or they will be served via cdn
  if ( options.cdn is true ) or ( options.bundle is true )
    src = src.concat paths.dependencies.bower.folderToCleanup

  del src
