bug#34789: Scan of regexp mistakes

[Eli Zaretskii]

> From: Davis Herring <herring@lanl.gov>
> Date: Fri, 8 Mar 2019 13:46:38 -0700
> 
> This style of code is rare, and will if anything become rarer still in 
> C++20, when code in a header file that uses a particular specialization 
> (e.g., std::vector<A>) can be put into a module that is compiled only 
> once.  Even if someone were doing this, mantemp.el could at most 
> generate the one indicated line in templates.cxx _after_ the very 
> similar line in foo.hxx was added in some other fashion.
> 
> Hope this helps clarify,

Thanks, it does.  I think we indeed should move this package into
obsolete/.