Software references in the code but the ref is ignored by the compiler

It occurred to me today, while doing a little a little catch-up of the forum, how convenient it would be to have a reference remark (meta-bookmark?), or pointer to a function, variable, or “unreadable” code embedded right there in the code!
Purpose is to help document the code in explicit ways, mostly to help future self and/or others trying to read and understand the code.
Using a simple mark that is a pointer to the variable, function, and etc and the linked location to that remark would require the compiler writers a little extra work but the advantages to this could be vast.
Deciding whether that reference mark is of fixed type, variable type, or etc would require some discussion while always allowing future expansion.
I picture usage to all along these lines:

  1. you’re reading/studying some code, regardless of who wrote it or who is doing the reading, a bookmark can allow the reader to a) maintain his place where is reading, and jumping to the variable definition, for example, and then jump back to the exact spot where he was reading.
    This would also help enormously if that code has multiple writers.
    It would also be part of the (self?) documentation of the code of whatever size it is.
    Oh, this is implemented in a very clunky way with some developer environments but I’m hoping for something simpler use and easier to implement.
    Julia is the perfect environment to implement such an idea. It might be akin to a simpler view a github library of routines.
    Development of the “meta-bookmark” could easily be implemented in stages with all the easy stuff done first.