docs: function engine(url) {
              var ret;
  
              var parts = /^(\w+):/.exec(url);
              if (!parts) {
                  d.fatal("Invalid engine URI", url);
              }
              try {
                  var Engine = angular.injector(['ng', 'coa.store']).get('Engine' + parts[1].ucfirst());
                  ret = new Engine(url);
              } catch(e) {
                  d.fatal("Unable to instantiate engine for URI", url, e);
              }
  
              d('STORE', 'Creating an engine for URI', url, ':', ret);
  
              return ret;
          }