Below is the API for the OCaml standard library. It's directly copied over from the OCaml Manual, formatted to the Reason syntax and styled accordingly. The API docs are work-in-progress; we'll be polishing these gradually!
If you're targeting JavaScript, the API docs for BuckleScript includes all of below, plus JS-specific APIs.
module Printast: sig .. end
val interface : Format.formatter -> Parsetree.signature_item list -> unit
val implementation : Format.formatter -> Parsetree.structure_item list -> unit
val top_phrase : Format.formatter -> Parsetree.toplevel_phrase -> unit
val expression : int -> Format.formatter -> Parsetree.expression -> unit
val structure : int -> Format.formatter -> Parsetree.structure -> unit
val payload : int -> Format.formatter -> Parsetree.payload -> unit