There are no "Zsh" (or "Z-shell") books in print, or even announced! There is one from APress ("From Bash to Z Shell") but it doesn't cover Zsh well (in spite of having Z shell creators as authors).
I want a Z shell book, maybe "Programming Z Shell". I would suggest O'reilly approach the ZSH creators and solicit a book from them. Another potential author is Stephane CHAZELAS . (I've been reading his posts on NNTP comp.unix.shell for years, and he knows shell and knows how to explain shell.
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