Looks like they both operate on the same thing (the CV*) to me. (If not, please explain, since I'm not very familiar with this stuff.) So the question is why does Perl and your function use different tests to determine the same thing? 
#define CvROOT(sv)      ((XPVCV*)SvANY(sv))->xcv_root_u.xcv_root
#define CvXSUB(sv)      ((XPVCV*)SvANY(sv))->xcv_root_u.xcv_xsub
 
#define CvOUTSIDE(sv)   ((XPVCV*)SvANY(sv))->xcv_outside

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In reply to Re^4: How do I test the validity of a CODE reference? by ikegami
in thread How do I test the validity of a CODE reference? by pilap

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