Re: file-readable-p returns t for empty string

[Richard Stallman]

    "Absolute file name" is a widely-used notion, and as such, is mostly 
    known to programmers, even if its exact definition is sometimes a bit 
    vague.  An empty string is a strange file name to include in that 
    category, so programmers will probably not expect that.

Yes, exactly.  The idea of defining "" as an absolute file name is
absurd, so there is no need to investigate whether it would "work".
We won't do this.