I wanted to write an article about dualvars and list all the existing dualvars in Perl. I know only about $! but Scalar::Util claims that even that is not dualvar. 
say isdual $!

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prints 1 so I doc of Scalar::Util incorrect.

Are there other dualvars in perl core? Do you know any dualvars in CPAN modules?

In reply to Dualvars besides $! by szabgab

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