How do I make an extern function?

Simen kjaeraas simen.kjaras at
Tue Jun 29 03:24:42 PDT 2010

BCS <none at> wrote:

> The issue is that the function called from module a is
> _D1a3fooFZv where the function defined in module b is
> _D1b3fooFZv ('a' <-> 'b') so they aren't the same function. extern(C)  
> works because C doesn't mangle names so the function is foo in both  
> cases.

I know. I just react to 'extern void foo();' being treated as a
function that must be in a. I would expect extern to indicate it lies
elsewhere in the program.

> You can resolve this by having a a.di file with the extern foo(); in it  
> (DMD has a flag to generate such a file for you). OTOH without knowing  
> what you are doing, I can't tell if this is the correct solution.

I'm trying to create a framework in which the user may provide his own
foo( ), so the name of module b is impossible to know.

torhu <no at spam.invalid> wrote:
>   You could always create a b.di file, if that doesn't defeat the  
> purpose.

Jonathan M Davis <jmdavisprog at> wrote:
> Um, extern isn't needed in D. All you need to do is make the function  
> public and then import the module.

If only life were easy, eh? Module b is user-supplied, so I can't import


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