---
description: LHS reference of variable/property/element.
---

# lvalue

[JS](../../..) ⟩ [statement](../../statement) ⟩ [expression](../../statement/expr) ⟩ [operator](..) ⟩ [term]() ⟩ lvalue

{% hint style="success" %}
([expr](../../statement/expr "mention"))&#x20;

[variable](../../../variable "mention") <mark style="color:yellow;">**/**</mark> (object) [prop](../../../val/obj/prop "mention") <mark style="color:yellow;">**/**</mark> (array) [element](../../../val/builtin/arr/element "mention") that appears on the <mark style="color:yellow;">**left side**</mark> of an [assign](../assign "mention").&#x20;

:u6307: <mark style="color:yellow;">**synonyms**</mark>： "<mark style="color:purple;">**assignment target**</mark>"
{% endhint %}

{% tabs %}
{% tab title="⭐️ 重點" %}
{% hint style="info" %}
[delete](../../../val/obj/prop/create/delete "mention") expects its <mark style="color:yellow;">**operand**</mark> to be an <mark style="color:purple;">**lvalue**</mark>, <mark style="color:red;">**if**</mark> it is <mark style="color:red;">**not**</mark>**&#x20;**<mark style="color:yellow;">**an**</mark>**&#x20;**<mark style="color:purple;">**lvalue**</mark>, the operator <mark style="color:yellow;">**takes**</mark>**&#x20;**<mark style="color:red;">**no**</mark>**&#x20;**<mark style="color:yellow;">**action**</mark> and <mark style="color:yellow;">**returns**</mark>**&#x20;**<mark style="color:green;">**true**</mark>.
{% endhint %}

{% hint style="success" %}
<mark style="color:purple;">**lvalue**</mark> can be used in [of](../../statement/loop/for/of "mention") / [in](../../statement/loop/for/in "mention") loop.
{% endhint %}
{% endtab %}

{% tab title="👥 相關" %}
* [lhs](../../../variable/access/lhs "mention")
* <mark style="color:purple;">**lvalue**</mark> can be used in a [of](../../statement/loop/for/of "mention") / [in](../../statement/loop/for/in "mention") loop.
{% endtab %}

{% tab title="📗 參考" %}
* [ ] [javascript-the-definitive-guide](../../../../master/ref/javascript-the-definitive-guide "mention") ⟩&#x20;
  * [ ] 4.7.1&#x20;
  * [ ] 4.13.4 The delete Operator
{% endtab %}

{% tab title="📘 手冊" %}
* [for...in](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in)&#x20;
  * ⟩ [parameters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in#parameters) (for "assignment target")
{% endtab %}
{% endtabs %}
