The base class variational::base_family has no virtual methods and the one function it does define uses no member variables or functions, so can be made standalone outside of the class. Therefore, base_family should be removed.
If the intent was to somehow pull down some of the functionality from the subclasses, then this issue should be repurposed to do that.
The base class
variational::base_familyhas no virtual methods and the one function it does define uses no member variables or functions, so can be made standalone outside of the class. Therefore,base_familyshould be removed.src/stan/variational/base_family.hppwrite_error_msg_()into its own file and rename without suffix_families/normal_meanfield.hppandfamilies/normal_fullrank.hpp:base_familywrite_error_msg_to include and call new functionIf the intent was to somehow pull down some of the functionality from the subclasses, then this issue should be repurposed to do that.