$ ocamlfind printppx
Usage: ocamlfind query        [-help | other options] <package_name> ...
   or: ocamlfind ocamlc       [-help | other options] <file> ...
   or: ocamlfind ocamlcp      [-help | other options] <file> ...
   or: ocamlfind ocamlmklib   [-help | other options] <file> ...
   or: ocamlfind ocamlmktop   [-help | other options] <file> ...
   or: ocamlfind ocamlopt     [-help | other options] <file> ...
   or: ocamlfind ocamloptp    [-help | other options] <file> ...
   or: ocamlfind ocamldep     [-help | other options] <file> ...
   or: ocamlfind ocamlbrowser [-help | other options]
   or: ocamlfind ocamldoc     [-help | other options] <file> ...
   or: ocamlfind install      [-help | other options] <package_name> <file> ...
   or: ocamlfind remove       [-help | other options] <package_name>
   or: ocamlfind printconf    [-help] [variable]
   or: ocamlfind lint         [-help] <file>
   or: ocamlfind list
   or: ocamlfind pkg/cmd arg ...
Select toolchain with:
  ocamlfind -toolchain <t> <command>
Abbreviations:
  e.g. ocamlfind opt instead of ocamlfind ocamlopt