Re: should `minibuffer-complete' use `abbreviate-file-name'?

[Richard Stallman]

    His usage:

     FROM: Any easy-to-type and mnemonic regexp that matches
           a syntactically valid directory name, whether or not
           such a directory exists. Example: "^/proj1".

     TO:   An (absolute) name of an existing directory.
           Example: "/a/very/long/dir/name/to/my/project".

That is definitely not what this feature is meant for.
It isn't meant for expanding abbreviations.
It is meant for replacing long names with equivalent short ones.

If he wants a short way to enter /a/very/long/dir/name/to/my/project,
he should make ~/proj1 a symlink to it.  Then he can use the
abbreviation ~/proj1 in EVERY program.