in reply to Test::Deep - weak references are not implemented
That's kinda strange, as (IIRC) weak refs were introduced with v5.6.0. Also, FWIW, I can't replicate the problem with v5.8.4 (on Linux) with any combination of Scalar::Util 1.13 / 1.19 and Test::Deep 0.096 / 0.100.
Other than that, there's a note in the current Test::Deep CHANGES file:
0.099
Don't explode on perl's that don't have weakrefs. If they're not available, just don't weaken the refs. It means refs can be cached for longer than desirable but it's better than explodiing.
This doesn't fix all of te problems with perl 5.005 but I'm pushing it out because the previous version number upsets CPAN.pm.
IOW, the current version should work (even with perls that truly don't support weak refs...).
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