code: function stringifyStrictObject( v , runtime )
  {
  	var i , iMax , keys ;
  	
  	runtime.str += '{' ;
  	
  	keys = Object.keys( v ) ;
  	
  	for ( i = 0 , iMax = keys.length ; i < iMax ; i ++ )
  	{
  		if ( v[ keys[ i ] ] !== undefined )
  		{
  			if ( i ) { runtime.str += ',' ; }
  			stringifyString( keys[ i ] , runtime ) ;
  			runtime.str += ':' ;
  			stringifyAnyType( v[ keys[ i ] ] , runtime ) ;
  		}
  	}
  	
  	runtime.str += '}' ;
  }
docs: Faster than stringifyStrictObjectMemory(), but cost a bit more memory