Why would a programmer need to defend against this? There's no harm (except performance-wise) in Perl locking an SV internally while it's mucking with the SV's innards.

If two threads are mucking with the innards of the same SV at the same time, you have a huge problem. Locking the SV while mucking with the innards would solve that problem with no side-effects.

If you already have safeguards in place to prevent the two threads from mucking with the innards of the same SV at the same time, then this internal locking is effectively a no-op.

In reply to Re^4: A faster?, safer, user transparent, shared variable "locking" mechanism. by ikegami
in thread A faster?, safer, user transparent, shared variable "locking" mechanism. by BrowserUk

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