Where to put the doxygen comment blocks for an internal library - in H or in CPP files?
The common sense tells that the Doxygen comment blocks have to be put in the header files where the classes, structs, enums, functions, declarations are. I agree that this is a sound argument for a libraries that are mean to be distributed without its source (only headers and libs with object code).
BUT...I've been thinking of the exact opposite approach when I'm developing an internal to the company (or as a side project for myself) library that will be used with its full source code. What I propose is to put the large comment blocks in the implementations files (HPP, INL, CPP, etc) in order NOT to clutter the inteface of the classes and functions declared in the header.
Pros:
- Less clutter in the header files, only categorizing of the functions can be added.
- The comment blocks that are previewed when Intellisense for example is used doesn't clash - this is a defect that I have observed when I have a comment block for a function in the .H file and have its inline definition in the same .H file but included from .INL file.
Cons:
- (The obvious one) The comment blocks are not in the header files where the declarations are.
So, what do you think and possibly suggest?
Answer
Put the documentation where people will read and write it as they are using and working on the code.
Class comments go in front of classes, method comments in front of methods.
That is the best way to make sure things are maintained. It also keeps your header files relatively lean and avoids the touching issue of people updating method docs causing headers to be dirty and triggering rebuilds. I have actually known people use that as an excuse for writing documentation later!