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The book itself has great content, however, I wasn't really happy with the quality of the printing on the book, there are so many pages which the printing looks horrible, that's the only reason I'm giving 3 stars.
Like the other Effective books I've read (C++ and Java), this book is written by someone who both understands the language deeply and is able to come up with great examples for showing its more subtle aspects. Required reading once you've programmed TypeScript for a few months!