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Re^4: how ! operator works

by ikegami (Pope)
on Feb 04, 2011 at 20:48 UTC ( #886297=note: print w/ replies, xml ) Need Help??


in reply to Re^3: how ! operator works
in thread how ! operator works

So I looked at the code to answer your question. It looks like it's a hack, not a magical value. The refcount can go down, but it gets reset back to the max for SvIMMORTAL variables (the true, the false, the undef and a special internal thing called "placeholder").


Comment on Re^4: how ! operator works
Re^5: how ! operator works
by arkturuz (Curate) on Feb 04, 2011 at 22:23 UTC
    So I looked at the code to answer your question.

    Thanks! I searched the code myself today with no luck. I postoponed it for the weekend but now you have resolved this, I'll just have to stick to something else to do :)
      My answer is more or less an educated guess. If you want to look around to confirm or for fun, PL_sv_no is the SV returned when a builtin wants to return something false. An interesting puzzle would be to see if you can manage to lower the refcount and display it at the lower refcount using Devel::Peek's Dump.

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