Objects.clone()

Syntax

function clone<T>(object: T, mode: RecursionMode = 'shallow'): T

Example

import { Objects } from 'potence';

Objects.clone(5);                       // -> 5
Objects.clone([1, 2, 3]);               // -> [1, 2, 3]
Objects.clone({ why: 'hello there' });  // -> { why: 'hello there' }

class Dog {
    // private property, so Objects.clone() can't access it
    #superSecretProperty: string;

    constructor(name: string) {
        this.#superSecretProperty = name;
    }

    clone() {
        return new Dog(this.#superSecretProperty);
    }
}

Objects.clone(new Dog('try to clone this!'));
// -> Dog { #superSecretProperty: 'try to clone this!' }

Remarks

The behaviour of this function varies depending on the type of object that is passed in:

1. If the input value is a primitive or null, returns it unchanged. As these are value types, it will automatically be cloned.
2. If the input value has a clone() function, calls it and returns the result.
3. If the input value is an array, clones the array. If mode is “deep”, calls clone() on each array item.
4. Creates a new object literal and assigns all enumerable properties of object to it before returning it. If mode is “deep”, calls clone() on each property value first.

Note that this function can throw an error, for instance if object or one of its properties is an instance of a class constructor. In that case you probably want to implement a clone() function on the type.

If a property is declared as readonly, this function will silently skip it. Most of the time this will simply mean a computed property (i.e. a property with only a getter) which doesn’t need its value cloned anyway.