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in reply to Re: defined defined -- Bug or "Feature"?
in thread defined defined -- Bug or "Feature"?

You state that like you know it to be the case, but I couldn't see that behavior described in the documentation. Do you know this from the code?

Premature optimization is the root of all job security
  • Comment on Re^2: defined defined -- Bug or "Feature"?

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Re^3: defined defined -- Bug or "Feature"?
by dave_the_m (Monsignor) on Dec 24, 2015 at 09:33 UTC
    The docs say that it returns a boolean value, i.e. a true or false value. It would be surprising for a false value to also be undefined, as you would get 'undefined' warnings if you tried using operators on the results. This shouldn't warn:
    $x = defined($y) ^ defined($z);

    Dave.

Re^3: defined defined -- Bug or "Feature"?
by Anonymous Monk on Dec 24, 2015 at 09:29 UTC
    I guess he didn't (guess). It's easily tested...
    print defined( undef ) // 'n/a'; print defined( undef ) || 'n/a'; n/a