gExp ` , the `
MyRegExp ` species is the ` MyRegExp ` constructor. However, you might want to
overwrite this, in order to return parent ` RegExp ` objects in your derived
class methods:

js

    
    
    class MyRegExp extends RegExp {
      // Overwrite MyRegExp species to the parent RegExp constructor
      static get [Symbol.species]() {
        return RegExp;
      }
    }
    

Or you can use this to observe the copying process:

js

    
    
    class MyRegExp extends RegExp {
      constructor(...args) {
        console.log("Creating a new MyRegExp instance with args:", args);
        super(...args);
      }
      static get [Symbol.species]() {
        console.log("Copying MyRegExp");
        return this;
      }
      exec(value) {
        console.log("Executing with lastIndex:", this.lastIndex);
        return super.exec(value);
      }
    }
    
    Array.from("aabbccdd".matchAll(new MyRegExp("[ac]", "g")));
    // Creating a new MyRegExp instance with args: [ '[ac]', 'g' ]
    // Copying MyRegExp
    // Creating a new MyRegExp instance with args: [ MyRegExp /[ac]/g, 'g' ]
    // Executing with lastIndex: 0
    // Executing with lastIndex: 1
    // Executing with lastIndex: 2
    // Executing with lastIndex: 5
    // Executing with lastIndex: 6
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-get-regexp-@@species  ](https://tc39.es/ecma262/multipage/text-
processing.html#sec-get-regexp-@@species)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ ` RegExp ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp)
  * [ ` Symbol.species ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/species)

##  Help improve MDN

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