It appears that currently, COW is only used for certain copy operations--some of those in the regex engine, shared hash keys (or values?), and a few other places--but not currently simple scalars.

It looks like the proposal is to extend it's reach.

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Silence betokens consent.
Love the truth but pardon error.

In reply to Re^3: What is PERL_COPY_ON_WRITE Compile Option About by BrowserUk
in thread What is PERL_COPY_ON_WRITE Compile Option About by DeadPoet

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