c++ - Template metaprogramming rules of thumb -

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what rules of thumb should considered whenever might use template metaprogramming accomplish goal? , good example using template metaprogramming more efficient plain old code other libraries boost?

one helpful rule can think of have compilation error thrown close "true" problem possible. ways it's easier not deduce issue easier others use library deduce issue.

here's contrived version of mean:

template<typename type> struct convert{}; template<> struct convert<double>{ static const int value = d_coord; }; template<> struct convert<degree>{ static const int value = angle_coord; }; template<> struct convert<radian>{ static const int value = radian_coord; };

for you'll not salient description of compiler error attempting convert<int> when if had made first declaration forward declaration tell there no type defined "convert."

as far example, i'm afraid i'll have defer else. however, might want take @ loki. it's not boost sure awesome.


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