At the beginning of the Composing Functions subsection in Chapter 1 it says: “You’ve already done this kind of implicit function composition during several of the examples in this chapter …” and then a function using let bindings is shown. But let bindings haven’t been discussed yet (maybe an earlier version had some examples earlier).
Hi, thanks for calling this out! That was an oversight that slipped in as I was re-organizing some sections. I’ve gotten that revised and it will be fixed with the next beta update!