Re: [Boost-users] Library Developers Battling Cyclic Header Dependency

Subject: Re: [Boost-users] Library Developers Battling Cyclic Header Dependency
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2011-03-16 14:41:16

On 16/03/2011 18:45, Ryan wrote:
> In the boost library system certain libraries need to be compiled and
> linked into a project.  For example, libraries would need to be compiled
> to remove cyclic header dependencies.  In the boost library system I
> coundn't find any .cpp files that would indecate a compilable library.
> So how do library developers create compilable files in the boost
> libraries?  The following two files would need to be broken up and
> compiled to remove the dependencies, correct?
> Ryan
> //File A.hpp
> class B;
> class A {
>    double x;
> public:
>    B convertToB(void) {
>      return B(x);
>    }
> };
> //File B.hpp
> class A;
> class B {
>    double y;
> public:
>    A convertToA(void) {
>      return A(y);
>    }
> };

Just move the definitions of convertToB and convertToB to other files.
Whether they're headers or not is irrelevant (you'll need to qualify 
inline explicitly if they're in headers though).