I'm aware of PL_sv_undef and how it's used. It's besides the point. In Perl land, undef is undef is undef. There's only one case where I know where that doesn't hold (in open), and I believe that was a mistake (or a backwards compatibility solution).

In reply to Re^11: Use of uninitialized value in substr by ikegami
in thread Use of uninitialized value in substr by BrowserUk

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