yes, they are also globaller-than-global globals. you can see then in perlapi.h look for "pl_sv_". you don't ever overload them. you break everyone else's code when you change these values. in fact, this entire avenue is just off limits because you can't change the behaviour of undef, yes, and no without changing it for every piece of every module loaded, everywhere.

the only case where you could possibly, maybe, change these values would be during small, discrete sections of your own code where you overload your value on entering and remove the overload before calling any functions, magic or explict, and before exiting. you'd have to have vetted all your input values to know that nothing has been tied, overloaded, or somehow has get or set magic. The point to this paranoia is that the none of the code you've included from cpan or from the core distribution is going to expect that true, false, and undefined have changed. It will break all other code that depends on them.

In reply to Re^8: The Null Mull (or, when OO needs more O) by diotalevi
in thread The Null Mull (or, when OO needs more O) by brian_d_foy

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