It's always tempting to spend a lot of time on syntax, but in this case it may be justified. Syntactic brevity is a good part of the point of TDNR. And I'm on a train which is a good time to argue about syntax. Personally I think there are strong advantages to ".": * For record selectors, currently written (x r), writing r.x is exactly right * For these unary operators, r.x really does mean (abstractly) "select the x field from r" * And that is the way that "." is used for modules: "M.x" means "select the x function from module M" * You can think of qualified names for modules in the same way "Control.Monad" means pick the Monad module from the Control group. * It culturally fits with the way "." is used on OO languages What is the disadvantage? Well, Haskell already uses "." for composition. But * "." is already special. If you write M.x you mean a qualified name, not the composition of data constructor M with function x I merely propose to make it even special-er! I'll keep quiet about syntax now. Simon | -----Original Message----- | From: haskell-cafe-bounces@haskell.org [mailto:haskell-cafe- | bounces@haskell.org] On Behalf Of wren ng thornton | Sent: 18 November 2009 03:07 | To: Haskell Cafe | Subject: Re: [Haskell-cafe] Status of TypeDirectedNameResolution proposal? | | Neil Brown wrote: | > Having skimmed the page, it seems like the re-use of "." is one of the | > major difficulties of the proposal. Would it be possible to use "->"? | > It has been used for accessing members in C and C++, so it is not too | > unusual a choice. | | It's also the one that Perl went with. | | | > It is already special in Haskell so it wouldn't break | > anyone's code -- but do its other uses (case statements and lambdas) | > mean that it would cause problems in the grammar if re-used for TDNR? | | Given the other uses of -> in Haskell, I'm hesitant to suggest it | either. I seem to recall # is the option used by OCaml and a few other | functional-OO languages. So far as I know -XMagicHash is the only thing | that would conflict with that name so it seems far less invasive than . | or ->. Another option would be to use @ which is currently forbidden in | expressions, though that might cause issues with System F/Core. | | -- | Live well, | ~wren | _______________________________________________ | Haskell-Cafe mailing list | Haskell-Cafe@haskell.org | http://www.haskell.org/mailman/listinfo/haskell-cafe