Peteris Krumins has a new book, Perl One-Liners Explained. His new book is in the same style as his previous books on awk and sed, reviewed here and here.
All the books in this series are organized by task. For each task, there is a one-line solution followed by detailed commentary. The explanations frequently offer alternate solutions with varying degrees of concision and clarity. Sections are seldom more than one page long, so the books are easy to read a little at a time.
Programmers who have written a lot of Perl may still learn a few things from Krumins. In particular, those who have primarily written Perl in script files may not be familiar with some of the tricks for writing succinct Perl on the command line.
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