[MLton-user] bug with path variables in mlb files

[John Reppy]

You should probably allow multiple "." in path names and disallow  
pathnames
that start with "-".  Then you've covered the POSIX portable pathnames.

It would also be nice if one could directly specify a pathvar on the
command line, instead of having to create a pathmap file.

	- John

On Nov 6, 2007, at 8:42 AM, Matthew Fluet wrote:

> On Tue, 6 Nov 2007, Vesa Karvonen wrote:
>> I took the liberty of fixing this by allowing digits in path  
>> variables:
>>
>>  http://mlton.org/pipermail/mlton-commit/2007-November/002129.html
>>
>> So, just svn up, rebuild, install the compiler, and the problem  
>> disappears.
>>
>> -Vesa Karvonen
>>
>> On Nov 6, 2007 1:36 PM, John Reppy <jhr at cs.uchicago.edu> wrote:
>>> It appears that a path variable like $(SML3D_LIB) is not  
>>> considered a
>>> valid token by mlton. [...]
>
> I don't think there was ever a reason to disallow digits in path  
> variables.  I don't know that additional symbols would be  
> desirable, though I guess one could make the claim for them.   
> Vesa's patch makes the lexical conventions for MLBasis files:
>
> pathvar="$("([A-Z_][A-Z0-9_]*)")";
> filebase=({pathvar}|[-A-Za-z_0-9])+;
> fileext=({pathvar}|[-A-Za-z_0-9])+;
> filename={filebase}("."{fileext})*;
> arc=({pathvar}|{filename}|"."|"..");
> relpath=({arc}"/")*;
> abspath="/"{relpath};
> path={relpath}|{abspath};
> file={path}{filename};
>
> That falls short of the full range of UNIX paths (since we rule out  
> most special characters).  But, one can also use put file names in  
> " (quotes) for an arbitrary file name, in which case they are lexed  
> as SML string constants.
>