/usr/include/boost/fusion/functional/ is in libboost1.62-dev 1.62.0+dfsg-5.
This file is owned by root:root, with mode 0o755.
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/usr/include/boost/fusion/functional/adapter/
/usr/include/boost/fusion/functional/adapter.hpp
/usr/include/boost/fusion/functional/adapter/detail/
/usr/include/boost/fusion/functional/adapter/detail/access.hpp
/usr/include/boost/fusion/functional/adapter/fused.hpp
/usr/include/boost/fusion/functional/adapter/fused_function_object.hpp
/usr/include/boost/fusion/functional/adapter/fused_procedure.hpp
/usr/include/boost/fusion/functional/adapter/limits.hpp
/usr/include/boost/fusion/functional/adapter/unfused.hpp
/usr/include/boost/fusion/functional/adapter/unfused_typed.hpp
/usr/include/boost/fusion/functional/generation/
/usr/include/boost/fusion/functional/generation.hpp
/usr/include/boost/fusion/functional/generation/detail/
/usr/include/boost/fusion/functional/generation/detail/gen_make_adapter.hpp
/usr/include/boost/fusion/functional/generation/make_fused.hpp
/usr/include/boost/fusion/functional/generation/make_fused_function_object.hpp
/usr/include/boost/fusion/functional/generation/make_fused_procedure.hpp
/usr/include/boost/fusion/functional/generation/make_unfused.hpp
/usr/include/boost/fusion/functional/invocation/
/usr/include/boost/fusion/functional/invocation.hpp
/usr/include/boost/fusion/functional/invocation/detail/
/usr/include/boost/fusion/functional/invocation/detail/that_ptr.hpp
/usr/include/boost/fusion/functional/invocation/invoke.hpp
/usr/include/boost/fusion/functional/invocation/invoke_function_object.hpp
/usr/include/boost/fusion/functional/invocation/invoke_procedure.hpp
/usr/include/boost/fusion/functional/invocation/limits.hpp