[MLton] Windows ports and paths

[Andreas Rossberg]

> > For instance, what should #arcs(fromString "A:") deliver? (I went for
> > [""], in analogy to "/").
>
> That was a mistake I think.
> "A:" = "A:.", that's what MLton does now, so arcs=[] and isAbs=false.
>
> I also think this is what the standard intended.
> If you allow "\" to be absolute, then it stands to reason "" is "." and by
> analogy "E:\" is absolute and "E:" is "E:."

Oh, I didn't say "A:" ought to be absolute. Just that it contains an empty
arc. So isAbs = false but arcs = [""]. I don't think that would be any less
consistent (consider that "/" = "/.", although "/" contains the empty arc).

Anyway, I just checked again, and contrary to what I (and my notes) said, it
actually seems that I also went for arcs=[] in the end. I don't remember the
reason... :)

Incidently, I think it would have been preferable if the Basis spec had
defined arcs "/" = [] in the first place.

  - Andreas