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functionscopedfunction-calls

Mutually Dependent Function Declarations in Functions

Is it possible to have two or more outer function-scoped functions that have mutual call dependencies on each other?

I'm asking because 

void main(string args[]) {
    int x = 42;
    void a() {
        // do something with x
        b();
    }
    void b() {
        // do something with x
        a();
    }
}

errors in DMD as

/home/per/Work/justd/t_funs.d(5): Error: undefined identifier b

If not is this an unresolved issue or a feature?

Solution

  • you can declare the delegate b before a and then assign b

    void main(string args[]) {
    int x = 42;
    void delegate() b;
    void a() {
        // do something with x
        b();
    }
    b = delegate void () {
        // do something with x
        a();
    };
}

    it'll require a refactor but not as bad as throwing it all in structs