unnamed namespace

[ModShop]

Say I have an unnamed namespace that contains some functions local to a certain file. Is it posable to declare the functions inside of the namespace and define them elseware, or must they be defined inside of the namespace?
ex.

namespace {
    void func();}

int main(){
    func();
    return 0;}

void func(){
    /*code*/}

Is this valid? Is there a valid way of doing it if it isn't?
Thanks

[firedraco]

Yes, but like all functions you must respect scope:

namespace {
    void func();
}

void func(); //this is a different scope (global scope)

int main() {
    func(); //this would print 1
}

namespace {
    void func() {
        std::cout<<1;
    }
}

[ModShop]

So I just use the namespace keyword again when defining the function? That makes sense. Thanks!