A way to mark symbols as private

[Akuli]

Currently all functions and structs are made available for other files to import. There should be a way to make functions and structs be visible only within the current file.

Maybe static?

static def internal_util_function() -> int:
    return 123

static struct PrivateStruct:
    x: int
    y: int

def public_function() -> int:
    return internal_util_function() * 2

struct PublicStruct:
    message: byte*
    line: int

[littlewhitecloud]

I think on the contrary, you can use the "extern" keyword to decide which functions need to be exported. Then other variables, functions, structs of the current file will not be accessed.And then, they will be private

[littlewhitecloud]

def internal_util_function() -> int:
    return 123

static struct PrivateStruct:
    x: int
    y: int

extern def public_function() -> int:
    return internal_util_function() * 2

extern struct PublicStruct:
    message: byte*
    line: int

[Akuli]

I think on the contrary, you can use the "extern" keyword to decide which functions need to be exported. Then other variables, functions, structs of the current file will not be accessed.And then, they will be private

So basically, everything is private by default, and you can use a keyword like extern to make public things. This seems like a good idea.

I think I will probably name the keyword public instead of extern, for two reasons:

• With extern many people would think: "what does the extern keyword do again? Ah now I remember, it makes the thing public."
• The extern keyword has a different meaning in C. Jou's declare and C's extern both correspond to the same idea: they tell the linker that something exists without defining it.

[Akuli]

More possible keywords to use for this:

• export, same as in JavaScript
• pub, same as in Rust

[Akuli]

• I think I don't like export, because it would get confused with __declspec(DLLEXPORT) in windows.
• pub is a bit too short considering Jou's goals: we need readability.

[sumeshir26]

I think global or public will be the most clear

[Moosems]

public looks fine to me. I understood extern just fine and would be a little disappointed if someone couldn't deduce its meaning.

[Akuli]

It seems that everyone is happy with public. I will use it when I eventually get around to implementing this :)

[Akuli]

How about a decorator?

@public
def add(x: int, y: int) -> int:
    return x + y

[Moosems]

I like that, but if it isn't written in Jou that would feel a bit too automagic-y for a decorator.