The Array[@@species] accessor property returns the Array constructor.
Array[Symbol.species]
The Array constructor.
The species accessor property returns the default constructor for Array objects. Subclass constructors may override it to change the constructor assignment.
The species property returns the default constructor function, which is the Array constructor for Array objects:
Array[Symbol.species]; // function Array()
In a derived collection object (e.g. your custom array MyArray), the MyArray species is the MyArray constructor. However, you might want to overwrite this, in order to return parent Array objects in your derived class methods:
class MyArray extends Array {
// Overwrite MyArray species to the parent Array constructor
static get [Symbol.species]() { return Array; }
} | Specification | Status | Comment |
|---|---|---|
| ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'get Array [ @@species ]' in that specification. | Standard | Initial definition. |
| ECMAScript Latest Draft (ECMA-262) The definition of 'get Array [ @@species ]' in that specification. | Draft |
| Desktop | ||||||
|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | |
| Basic support | ? | ? | 48 | ? | ? | ? |
| Mobile | |||||||
|---|---|---|---|---|---|---|---|
| Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | iOS Safari | Samsung Internet | |
| Basic support | ? | ? | ? | 48 | ? | ? | ? |
| Server | |
|---|---|
| Node.js | |
| Basic support | 6.5.0
|
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/@@species