On Thu, Sep 24, 2009 at 14:39, Eelco Dolstra <e.dols...@tudelft.nl> wrote:
>> IIUC Nicolas’ proposal is more flexible than ‘or’, because
>> “as.a.b.c or default” could mean any one of:
>>
>> - as.{a.b.c ? default}
>> - as.a.{b.c ? default}
>> - as.a.b.{c ? default}
>
> Mine also allows that:
>
> - as.a.b.c or default
> - (as.a).b.c or default
> - (as.a.b).c or default
>
> I.e. simply using the parentheses - no new syntax required.
>
> The idea is that the "." operator is changed from `expr "." attrname' to `expr
> "." attrpath ("or" expr)?'. So putting parenthesis around as.a or as.a.b
> gives
> you two applications of the "." operator, one without a default and one with a
> default.
or changed to:
select:
expr "." "{" attrpath "?" expr "}"
| expr "." attrname
IMO, this is an implementation reason which does not have a large
weight in this discussion unless a limitation exists (which is not the
case).
--
Nicolas Pierron
http://www.linkedin.com/in/nicolasbpierron
_______________________________________________
nix-dev mailing list
nix-dev@cs.uu.nl
https://mail.cs.uu.nl/mailman/listinfo/nix-dev
