---
description: 🚧 under construction
---

# type

[JS](..) ⟩ [value]() ⟩ type

{% hint style="warning" %}
🚧
{% endhint %}

{% tabs %}
{% tab title="⭐️ 重點" %}
{% hint style="warning" %}
there is <mark style="color:red;">**no**</mark> <mark style="color:purple;">**type**</mark> <mark style="color:yellow;">**associated**</mark> with [declare](../variable/declare "mention"):exclamation:
{% endhint %}

{% hint style="info" %}
The <mark style="color:yellow;">**operands**</mark> of [compare](../grammar/op/relational/compare "mention") may be <mark style="color:yellow;">**of**</mark>**&#x20;**<mark style="color:red;">**any**</mark> <mark style="color:purple;">**type**</mark>.
{% endhint %}
{% endtab %}

{% tab title="🔴 主題" %}
* <mark style="color:yellow;">**main topics**</mark>
  * [name](type/name "mention")
  * [custom-type-name](type/name/custom-type-name "mention")
  * [Broken link](broken-reference "mention")
* <mark style="color:yellow;">**type terms**</mark>
  * [falsy](type/falsy "mention")
  * [static](type/term/static "mention")
  * [dynamic](type/term/dynamic "mention") - JS is a dynamically typed language.
* <mark style="color:yellow;">**value types**</mark>
  * [prim](prim "mention")
    * [str](prim/str "mention") <mark style="color:yellow;">**/**</mark> [num](prim/num "mention") <mark style="color:yellow;">**/**</mark> [boolean](prim/boolean "mention")
  * [obj](obj "mention")
    * [class](class "mention") <mark style="color:yellow;">**/**</mark> [arr](builtin/arr "mention") <mark style="color:yellow;">**/**</mark> [set](builtin/set "mention") <mark style="color:yellow;">**/**</mark> [map](builtin/map "mention")
* <mark style="color:yellow;">**helper functions**</mark>
  * [type-functions](type/type-functions "mention")
{% endtab %}

{% tab title="👥 相關" %}
* [typeof](type/name/typeof "mention") <mark style="color:yellow;">**determines**</mark> the [type](type "mention") of a [](<> "mention"). (:point\_right: [name](type/name "mention"))
* [typename](type/name/typename "mention")
* [typescript](../../appendix/typescript "mention") is a JavaScript dialect that checks types.
{% endtab %}

{% tab title="📗 參考" %}
* [ ] Eloquent JavaScript > [Types](https://eloquentjavascript.net/08_error.html#h_k7niieKEJG)
{% endtab %}

{% tab title="📘 手冊" %}
* [typeof](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/typeof)
* [instanceof](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/instanceof)
{% endtab %}

{% tab title="🚧" %}
* [ ] type conversion table
* [ ] what is "type" in JS? 🚧
* [ ] how to determine a value's "type"? 🚧
{% endtab %}
{% endtabs %}
