archives

« Bugzilla Issues Index

#3280 — 9.1.2 [[SetPrototypeOf]] Contains unreachable steps


Substeps of 8 are unreachable in the latest draft, and step 7 is a duplicate of step 2.

Step 2: Let extensible be the value of the [[Extensible]] internal slot of O.
Step 5: If extensible is false, then return false.

Step 7: Let extensible be the value of the [[Extensible]] internal slot of O.
Step 8: If extensible is false, then (substeps)

[[Extensible]] is not modified in this algorithm, so if extensible is false, then it shouldn't be checked again.


IMO, steps 7 & 8 should just be removed, since they just duplicate steps 3,4,5 in a different order.


Proxy handlers executed during the prototype chain traversal (step 6.b.ii) can change the [[Extensible]] internal slot, see bug 2489.


Thanks, André. My mistake.