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

[Eli Zaretskii]

On 28 Feb 2002, David Kastrup wrote:

> The question would be what semantics about a file name being absolute
> file-name-absolute-p should be checking for, and what semantics about
> a file name being absolute expand-file-name should provide, and
> whether those are necessarily the same.

"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.

> Currently the online docs of
> file-name-absolute-p are as vague as can be about it: they just state
> something by example, and also say that this example is only valid
> for Unix systems.

I think that's intentional: Richard didn't want system-dependent stuff in 
a doc string.  But that vagueness does not mean that we can add anything 
we like to the definition, I think.