求助关于jQuery源码中createOptions函数的问题

Question

var optionsCache = {};// Convert String-formatted options into Object-formatted ones and store in cachefunction createOptions( options ) {var object = optionsCache[ options ] = {};jQuery.each( options.match( core_rnotwhite ) || [], function( _, flag ) {object[ flag ] = true;});return object;}createOptions('once momery');这个函数执行后,为什么optionsCache[ options ]={once:true,momery:true},我想知道的是他为什么和object的值一样，可是我在each外单独改变object的值，optionsCache[ options ]却不跟着改变？？