docs: function getRootChildren( root, libs, com ) {
    var src = ( root.attribs.src || "" ).trim( );
    if ( src.length > 0 ) {
      if (!libs.fileExists( src )) {
        libs.fatal( "File not found: \"" + src + "\"!" );
      }
      // Add a compilation dependency on the include file.
      libs.addInclude( src );
      var content = libs.readFileContent( src );
      root.children = libs.parseHTML( content );
    }
  }