[MLton-user] Re: MLton OS.Path under Windows [MLton-user Digest, Vol 27, Issue 6]

[Andreas Rossberg]

On Nov 14, 2008, at 10.01h, John Reppy wrote:

> Looking at the OS.Path specification, there is clearly an  
> inconsistency in the definition of
> absolute paths on Windows.  The confusion arises because Windows  
> has the notion of a path
> that is absolute relative to the current volume (but not strictly  
> absolute, since changing
> the volume changes its meaning).  I'm not sure what the correct fix  
> is.  The path of least
> resistance might be to change the specification of toString to read
>
> 	The exception Path is raised if vol <> "" and validVolume{isAbs,  
> vol} is false.

That would still allow fromString to deliver results that are not  
considered "valid". For paths that are perfectly sensible.

I think the simpler and more coherent fix is to simply change  
validVolume to allow empty volumes unconditionally on Windows.

> Alternatively, we could redefine the notion of absolute path on  
> Windows to require a
> valid volume.

I fear that this would require quite a few (incompatible) changes  
with the potential to break existing code in subtle ways.

Since we are at it, as I mentioned earlier (on the MLton list) I have  
a number of other issues with inconsistencies in OS.Path. If you are  
interested, I'd be happy to post them.

Best,
- Andreas