anchor.diff:  typedef String TemplateRenderer(context,
       {bool assumeNullNonExistingProperty, bool errorOnMissingProperty});
   
  -UserTag _HTML_GENERATE = new UserTag('HTML GENERATE');
  +final UserTag _HTML_GENERATE = new UserTag('HTML GENERATE');
   
   class Templates {
     TemplateRenderer indexTemplate;
  
positive.code:     String template = await _getTemplateFile(templatePath);
      // TODO: revisit, not sure this is the right place for this logic
      if (templatePath.contains('_footer') && _footer != null) {
        template = template.replaceAll(
            '<!-- Footer Placeholder -->', new File(_footer).readAsStringSync());
      }
      if (templatePath.contains('_head') && _header != null) {
        template = template.replaceAll(
            '<!-- Header Placeholder -->', new File(_header).readAsStringSync());
      }
      return template;
    }
  
negative.code:     }
    }
  
    String _partial(String name) => _partialTemplates[name];
  
    Future<TemplateRenderer> _loadTemplate(String templatePath) async {
      var templateContents = await _getTemplateFile(templatePath);
  