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Version: 3.28.0

handler.isExtensible()

The handler.isExtensible() method is a trap for Object.isExtensible().

Syntax​

new Proxy(target, {
  isExtensible(target) {
  }
});

Parameters​

The following parameter is passed to the isExtensible() method. this is bound to the handler.

  • target
    • : The target object.

Return value​

The isExtensible() method must return a boolean value.

Description​

The handler.isExtensible() method is a trap for Object.isExtensible().

Interceptions​

This trap can intercept these operations:

Or any other operation that invokes the [[IsExtensible]] internal method.

Invariants​

If the following invariants are violated, the trap throws a TypeError when invoked.

  • Object.isExtensible(proxy) must return the same value as Object.isExtensible(target).