Function templates can be explicitly instantiated (including those with inferred template parameters), but cxxheaderparser will not have it.
Per
|
tok = self.lex.token_if("class", "struct") |
all instantiations must be class or struct, and the TemplateInst type seems to assume this also.
https://en.cppreference.com/w/cpp/language/function_template explicit instantiation
https://coliru.stacked-crooked.com/a/15000b7567cd61ca <- compiles fine