I wonder if unary-plus existed before this use came about.
I'm pretty sure unary plus has been around since perl 1.0.0. I seriously doubt that writing '+1' in perl 1.0.0 resulted in an error. In fact, I've a hard time thinking of a programming language that doesn't have unary plus.

In reply to Re^2: About the + in front of a hashref that disambiguates from a code block. by JavaFan
in thread About the + in front of a hashref that disambiguates from a code block. by PoorLuzer

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