-----Original Message----- From: glasgow-haskell-users-bounces@haskell.org [mailto:glasgow-haskell-users-bounces@haskell.org] On Behalf Of Stefan O'Rear Sent: Friday, August 17, 2007 2:45 PM To: Christian Maeder Cc: Haskell Prime; GHC Users Mailing List; Isaac Dupree Subject: Re: Qualified identifiers opinion On Fri, Aug 17, 2007 at 12:53:11PM +0200, Christian Maeder wrote:
Hi Isaac,
just to give you a reply at all, see below. I reply glasgow-haskell-users@haskell.org since I'm not subscribed to haskell-prime. And I don't want to subscribe, because I'm more interested that Haskell becomes more stable (and standard). So here is my opinion:
1. The lexer should recognize keywords.
2. I would not mind if Haskel98 rejected all keywords that are also rejected by extensions, so that the lexer is extension independent. (Starting with Haskell98, removing conflicting identifiers as soon as I switch on valuable extensions does not make sense.)
3. I'm against qualified identifiers, with the unqualified part being a keyword like "Foo.where". (The choice of qualification should be left to the user, usually one is not forced to used qualified names.)
4. However, "Foo.where" should always be rejected and not changed to "Foo.wher e"! (Longest matching, aka "maximal munch", must not consider keywords!)
(see end of: http://www.haskell.org/onlinelibrary/lexemes.html#sect2.4)
I would not mind if a name "F. " is plainly rejected. It only makes sense, when a data constructor is the first argument of the composition operator "(.)"
Maybe "." and "$" as operators should require white spaces on both sides, since "$(" also indicates template haskell.
What's wrong with the status quo? Our current lexical rules *seem* complicated to newbies, but just like everything else in Haskell it carries a deep simplicity; having only one rule (maximal-munch) gives a certain elegance that the proposals all lack. I'd hate to see Haskell become complex all the way down just to fix a few corner cases; I see this pattern of simplicity degerating through well-intentioned attempts to fix things all over the language... Stefan I agree with Stefan, for the reasons he stated and for one additional reason: There would be a multitude of unintended behavior changes. Seth Kurtzberg Software Engineer Specializing in Security, Reliability, and the Hardware/Software Interface