It's a package variable, not a closure. In a sense it's a global variable, but notionally private to the package. There are other ways it could be done, but for a "simple" example it is expedient and not totally terrible.

Premature optimization is the root of all job security

In reply to Re^3: Logic expression evaluation not working. What am I doing wrong? by GrandFather
in thread Logic expression evaluation not working. What am I doing wrong? by perl_learner_2016

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