seal

The seal function recursively seals an object, preventing the addition or removal of properties.

Syntax

seal(obj): object

Parameters

Name	Type	Description
obj	object	Object to be sealed.

Return

Type	Description
object	Returns the sealed object.

Examples

const obj = { a: 1, b: { c: 2 } };
seal(obj);
// obj and obj.b cannot have properties added or removed

Notes

• Internally uses Object.seal recursively.
• Existing properties can still be modified, but not added or removed.
• Useful for protecting data structures from structural changes.

References

• MDN: Object.seal()