The Object isSealed() method
Find out all about the JavaScript isSealed() method of the Object object
Accepts an object as argument, and returns true
if the object is sealed, false
otherwise. Objects are sealed when they are return values of the Object.seal()
function.
Example:
const dog = {}
dog.breed = 'Siberian Husky'
const myDog = Object.seal(dog)
Object.isSealed(dog) //true
Object.isSealed(myDog) //true
dog === myDog //true
In the example, both dog
and myDog
are sealed. The argument passed as argument to Object.seal()
is mutated, and can’t be un-sealed. It’s also returned as argument, hence dog
=== myDog
(it’s the same exact object).
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