与使用makefile模块（Ocaml）的问题

Question

我在测试文件中使用我的模块时出现问题。我在这里创建了一个更简单的版本，它仍然复制了这个问题。

(* person.ml *) 
module Person = struct 
    type person = {name: string; age: int} 

    let create_person name age = {name=name; age=age} 

end 

---

(*makefile *) 
test: 
    ocamlbuild -pkgs oUnit,yojson,str,ANSITerminal test.byte && ./test.byte 

check: 
    bash checkenv.sh 

clean: 
    ocamlbuild -clean 

---

(* test.ml *) 
open OUnit2 
open Person 

let person = create_person "john" 40 

---

(* utop *) 
#use "person.ml" 
open Person 
let person = create_person "john" 40 

Output: val person : person = {name = "john"; age = 40} 

---

(* when I type in "make" in the terminal *) 

ocamlbuild -pkg oUnit test.byte && ./test.byte 
+ /Users/user/.opam/4.03.0/bin/ocamlc.opt -c -I /Users/user/.opam/4.03.0/lib/oUnit -I /Users/user/.opam/4.03.0/lib/ocaml -o test.cmo test.ml 
File "test.ml", line 4, characters 13-26: 
Error: Unbound value create_person 
Command exited with code 2. 
Hint: Recursive traversal of subdirectories was not enabled for this build, 
    as the working directory does not look like an ocamlbuild project (no 
    '_tags' or 'myocamlbuild.ml' file). If you have modules in subdirectories, 
    you should add the option "-r" or create an empty '_tags' file. 

    To enable recursive traversal for some subdirectories only, you can use the 
    following '_tags' file: 

     true: -traverse 
     <dir1> or <dir2>: traverse 

Compilation unsuccessful after building 4 targets (2 cached) in 00:00:00. 
make: *** [test] Error 10 

Answer 1

问题来自事实person_create是可访问的VI Person.create_person不是person_create。在ocaml中，文件已经是一个模块。因此，当您打开Person时，将打开其名称为person.ml的模块。在该模块中，您将创建一个名为Person的模块，您可以在其中定义person_create。因此，要么删除文件中的Person模块，要么输入“Person.create_person”而不是create_person。
当你在utop中测试时：#use指令就像是一个include。所以你失去了文件名，一旦你打开Person就可以直接访问person_create。