javascript连=符号

<script type="text/javascript">

var a = {n:1};

var b = a;

a = a.x = {n:2};

console.log(a.x);

console.log(b.x);

</script>

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a.x = a = {n:2};

a = a.x = {n:2};

javascript

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<span style="color: rgb(102, 102, 102); font-family: "Helvetica Neue", Helvetica, Arial, "PingFang SC", "Hiragino Sans GB", "WenQuanYi Micro Hei", "Microsoft Yahei", sans-serif; font-size: 13px; background-color: rgb(246, 246, 246);">a = a.x = {n:2}和a.x = a = {n:2}的结果是一致的原因是，属性访问表达式优先级高于“=”号，无论哪种赋值方式都是先执行a.x，</span>

javascript

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<span style="color: rgb(102, 102, 102); font-family: "Helvetica Neue", Helvetica, Arial, "PingFang SC", "Hiragino Sans GB", "WenQuanYi Micro Hei", "Microsoft Yahei", sans-serif; font-size: 13px; background-color: rgb(246, 246, 246);">所以a 指向是{n:1}，添加属性x之后,被重新赋值{n:2}对象。</span>

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