No recommendation for books, but if you're interested in the discussions on smartmatch, here's a thread that cropped up on the p5p mailing list and has been ongoing for a couple weeks relating to the fate of smartmatch in the next release (5.26.0).

In reply to Re^2: Are these Perl Textbooks Good? by stevieb
in thread Are these Perl Textbooks Good? by Svetlana

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