Automatic discovery for explicit template instantiations

[kwabenantim]

Summary

Currently template_substitutions need to be added to the yaml configuration to generate wrappers for each explicit instantiation of a class.

For example, Foo will need the yaml configuration below to generate wrappers for Foo<1>, Foo<2> and Foo<3>

Foo.hpp

template<unsigned SPACE_DIM>
class Foo {...}

Foo.cpp

...
template class Foo<1>;
template class Foo<2>;
template class Foo<3>;

config.yaml

...
template_substitutions:
  - signature: <unsigned SPACE_DIM >
    replacement: [[1], [2], [3]]

This configuration is needed because castxml only parses headers to extract the interface, but template instantiations are normally in cpp files.

One possible way to automate the discovery of template instantiations might be to add custom parsing logic in addition to the functionality provided by castxml.