import modules and function

[white pike]

i have a function inside file_extenion mod called open_csv (mod.rs) how do i import it in table_structure file?
this is my directory tree:

├──  file_extension/
│   ├──   mod.rs
│   └──   table_structure.rs
├──   lib.rs
└──   main.rs

[sullen scarab]

What program produced that second chart? If it's accurate then you have two mistakes here:

1. You have declared doubly-nested modules. You should not write mod file_extension inside of file_extension.rs; there should only be one mod in your entire project per module.
2. FileExtension is not pub, so it can't be used outside of the file_extension module. You need to write pub enum FileExtension or pub(crate) enum FileExtension

[white pike]

Sorry for the late replay;
this is cargo modules, cargo modules structure --lib

[white pike]

about the first state you said, i don't have any file_extensions.rs , i have a directory with name file_extension, mod file_extension is declared inside mod.rs

[sullen scarab]

that's the mistake

you have a mod file_extension; and a mod file_extension {. that makes you have two modules with the same name, nested

you do not declare modules inside of modules.

you should have only one mod per module you intend to have. it can be a mod foo; or a mod foo {, but you don't use both

[white pike]

mod file_extension; is inside lib.rs

[sullen scarab]

that's good.

[white pike]

do i remove it?

[sullen scarab]

no, you get rid o the mod file_extension {} that is inside file_extension/mod.rs

that is the extra module that you do not need.

[white pike]

but then i wouldn't have a module, right?

[sullen scarab]

no, mod file_extension; declares the module you want to have.

the contents of the module go directly in the corresponding file, file_extension/mod.rs

[white pike]

please bare with me i'm new to rust

[sullen scarab]

you do not also re-declare the module inside the file

you declare modules only once. not twice.

the string mod file_extension should appear in your program only once.

you do not need to declare the module once in lib.rs and again inside itself. that just makes two modules.

[white pike]

ohh so it is automatically a module?

[sullen scarab]

when you write mod file_extension;, with a ; instead of a {} you are saying: "please get the contents of this module from file_extension/mod.rs or from file_extension.rs"

your source files contain the contents of modules.

[white pike]

to be honest i'm more confused than ever, can i send you the repo link and tell me how can i declare the thing correctly?

[sullen scarab]

sure

(no DMs please.)

[white pike]

yeah sure

https://github.com/AymaneImr/just_testing

[sullen scarab]

it looks like you did the right thing to file_extension/mod.rs

https://github.com/AymaneImr/just_testing/blob/main/src/file_extension/table_structure.rs has the same problem, it has an extra mod table_structure {} in it

once you have fixed that too, you can do use super::FileExtension; inside table_structure.rs, and be able to use FileExtension::open_csv(). But, actually, maybe that function shouldn't be inside impl FileExtension? It doesn't use FileExtension at all.

then the path would be just super::open_csv or crate::file_extension::open_csv

[white pike]

mate thank you so much you saved me

now i understand those mistakes very well, i solved everything and now i'm able to call open_csv just as i wanted

[white pike]

yeah that's right i'm gonna improve it for sure

thanks man i appreciate your help