Another de-facto insecurity we need to fix in ES5

David-Sarah Hopwood david-sarah at
Fri Jun 19 11:51:22 PDT 2009

John Cowan wrote:
> David-Sarah Hopwood scripsit:
>> I support clarifying that [calling] Object.freeze prevents any further
>> mutation of all internal properties (it already prevents mutation
>> of __proto__, since that is a non-internal own-property). There's no
>> reason to treat [[Prototype]] or __proto__ as a special case.
> No, but an implementation might provide a magic function setPrototype
> instead, which merely freezing internal properties would not override.
> Making it clear that [[Prototype]] can't be changed covers this case
> as well.

I meant that Object.freeze should prevent mutating all internal properties
by any means.

David-Sarah Hopwood  ⚥

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