This may be interesting for some as Tezos is written in Ocaml:
Recently, the OCaml Software Foundation funded its translation to English. The book is available here:
Many thanks to Urmila for a translation of high quality.
The book is available as a PDF file, under the CC-BY-SA license. The source code for the various programs contained in the book are available for download, under the same license.
The book is structured in two parts. The first part is a tutorial-like introduction to OCaml through 14 small programs, covering many aspects of the language. The second part focuses on fundamental algorithmic concepts, with data structures and algorithms implemented in OCaml. This is also a nice way to learn a language!