如何在emacs、ubuntu上包含camlp4

Question

我有下面的源代码。你能帮助我为我的emacs配置camlp4，这样我就可以运行这段代码了吗？非常感谢

type term = V of string | F of string * term list

let rec symbols = function
  | V x -> [x]
  | F (f, ts) -> f :: [ g | t <- ts; g <- symbols t ]

let rec functions = function
  | V _ -> []
  | F (f, ts) -> f :: [ g | t <- ts; g <- functions t ]

Answer 1

您正在使用列表理解，这是Camlp4的一部分。要在终端仿真器中编译此代码，应键入

ocamlfind c -package camlp4.listcomprehension -syntax camlp4o -c a.ml

编译行与emacs或camlmode无关。但是，如果您想在toplevel中尝试此代码，则需要键入以下内容：

$ ocaml
    OCaml version 4.02.1

Findlib has been successfully loaded. Additional directives:
  #require "package";;      to load a package
  #list;;                   to list the available packages
  #camlp4o;;                to load camlp4 (standard syntax)
  #camlp4r;;                to load camlp4 (revised syntax)
  #predicates "p,q,...";;   to set these predicates
  Topfind.reset();;         to force that packages will be reloaded
  #thread;;                 to enable threads

# #camlp4o;;
/home/kakadu/.opam/4.02.1/lib/ocaml/dynlink.cma: loaded
/home/kakadu/.opam/4.02.1/lib/ocaml/camlp4: added to search path
/home/kakadu/.opam/4.02.1/lib/ocaml/camlp4/camlp4o.cma: loaded
        Camlp4 Parsing version 4.02.1

# #require "camlp4.listcomprehension";;
/home/kakadu/.opam/4.02.1/lib/ocaml/camlp4/Camlp4Parsers/Camlp4ListComprehension.cmo: loaded
# type term = V of string | F of string * term list;;
type term = V of string | F of string * term list
# let rec symbols = function
    | V x -> [x]
    | F (f, ts) -> f :: [ g | t <- ts; g <- symbols t ];;
val symbols : term -> string list = <fun>

$ cat ~/.ocamlinit
#use "topfind";;

要将camlp4安装到您的机器上，您需要为Ubuntu或opam预编译包。

Answer 2

谢谢你，卡卡度。我想我找到我的答案了。首先，我在我的ubuntu上安装了camlp4。

apt-get install camlp4
apt-get install camlp4-extra

然后，我在源代码中创建了一个文件.ocamlinit并添加：

#load "dynlink.cma";;
#load "camlp4of.cma";;

我认为这些步骤已经解决了我上面的问题，