whole_func_string: function(){
          var me = this,
              className = me.sourceClass ? me.sourceClass : '',
              methodName = me.sourceMethod ? '.' + me.sourceMethod + '(): ' : '',
              msg = me.msg || '(No description provided)';
  
          return className + methodName + msg;
      }
func_code_string: function(){
          var me = this,
              className = me.sourceClass ? me.sourceClass : '',
              methodName = me.sourceMethod ? '.' + me.sourceMethod + '(): ' : '',
              msg = me.msg || '(No description provided)';
  
          return className + methodName + msg;
      }
func_documentation_string: Provides a custom string representation of the error object. This is an override of the base JavaScript
  `Object.toString` method, which is useful so that when logged to the browser console, an error object will
  be displayed with a useful message instead of `[object Object]`, the default `toString` result.
  
  The default implementation will include the error message along with the raising class and method, if available,
  but this can be overridden with a custom implementation either at the prototype level (for all errors) or on
  a particular error instance, if you want to provide a custom description that will show up in the console.
  @return {String} The error message. If raised from within the Ext 4 class system, the error message will also
  include the raising class and method names, if available.