At the top of my elisp module, I want to do something as simple as:
(message (concat \"Loading \" (expand-file-name (current-elisp-module) \".\")))
You can use the variable load-file-name, which is set by the function load, documented as follows:
Full name of file being loaded by `load'.
As elaborated in the manual:
When Emacs is in the process of loading a file, this variable’s value is the name of that file, as Emacs found it during the search described earlier in this section.
Note: buffer-file-name as a routine does not work as you might expect it to.