Problem with getLayerAs for const pointers about tmxlite HOT 6 CLOSED

I think it's possible to fix this by casting away const, i.e. change lines 98-100 in Layer.hpp to

template <typename T>
const T& getLayerAs() const {
  return const_cast<Layer*>(this)->getLayerAs<T>();
}

but would appreciate an expert opinion on that!

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Interesting 🤔 When I get a chance I'll have to try it on other platforms to see if I get the same results. However I'm not a fan of the const_cast - I think the more correct way to fix it would be to create const overloads for each of the specialisations? If I happen to find an expert I'll ask them 😅

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Certainly would be do-able to create const overloads for each of the specialisations, if a little tedious. How about if it were swapped around - the specialisations are all for the const version? Then the non-const overload would cast to const (should always be safe), cast to the subclass, and then cast back to non-const (should also be safe because we know, within that same function, the pointer was to a non-const object in the first place)

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To be honest I'd prefer to do the work (it only has to be done once to be included in the library anyway) if it means the intended behaviour is explicit. After all it was my assumption based on implicit behaviour that all compilers would pick the correct specialisation which caused the bug in the first place 😉 I've made the changes and pushed them to the const_correctness branch - give it a try and see if it fixes it for you. If it does let me know and I'll merge it. Thanks!

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That certainly solved the problem I was having, 👍

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Good enough, thanks!

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