js_of_ocaml.ppx not being find

Question

我正在尝试运行js_of_eliom，但它似乎没有ppx_dering这是我制作时得到的信息：

js_of_eliom -ppx -c -package lwt -package js_of_ocaml.deriving -package js_of_ocaml.ppx  simple_pomodoro.eliom
Fatal error: exception Fl_package_base.No_such_package("js_of_ocaml.ppx", "")
make: *** [_client/simple_pomodoro.cmo] Error 2

当我进行ocamlfind查询js_of_ocaml.px时，我得到了这个：

ocamlfind: Package `js_of_ocaml.ppx' not found

但是我已经安装了ppx_dering，opam列表显示它：

ppx_deriving           3.3  Type-driven code generation for OCaml >=4.02

我和el capitan一起在mac osx里跑步（10.11）知道为什么会发生这种事吗？

编辑

哦，很抱歉我也安装了js_of_ocml，这是我的ocamlfind:中出现的内容

λ ~/ ocamlfind list | grep js_of_ocaml
js_of_ocaml         (version: 2.7)
js_of_ocaml.compiler (version: [distributed with js_of_ocaml])
js_of_ocaml.compiler.with_findlib (version: n/a)
js_of_ocaml.deriving (version: [distributed with js_of_ocaml])
js_of_ocaml.deriving.ppx (version: [distributed with js_of_ocaml])
js_of_ocaml.deriving.syntax (version: [distributed with js_of_ocaml])
js_of_ocaml.graphics (version: [distributed with js_of_ocaml])
js_of_ocaml.log     (version: [distributed with js_of_ocaml])
js_of_ocaml.ocamlbuild (version: [distributed with js_of_ocaml])
js_of_ocaml.syntax  (version: [distributed with js_of_ocaml])
js_of_ocaml.toplevel (version: [distributed with js_of_ocaml])
js_of_ocaml.tyxml   (version: [distributed with js_of_ocaml])
js_of_ocaml.weak    (version: [distributed with js_of_ocaml])

Answer 1

ppx_deriving是一个驱动程序，用于管理不同的Deriver。它本身并没有提供任何信息。您需要安装js_of_ocaml deriver，它是js_of_ocaml包的一部分：

opam install js_of_ocaml

结果你会得到它：

$ ocamlfind list | grep js_of_ocaml.ppx
js_of_ocaml.ppx     (version: [distributed with js_of_ocaml])
js_of_ocaml.ppx.internal (version: [distributed with js_of_ocaml])

Answer 2

我通过github在ocsigen问题报告中找到了解决方案https://github.com/ocsigen/eliom/issues/251

我做到了：

• 我已经重新安装了opam（v.1.2.2），重新初始化，安装4.02.3，utop&eliom。它仍然不起作用。然后我安装了deriving_px.3.0.0，就像你在SO中提到的那样，现在它运行得很好。Thx