On 2/2/07, Douglas Philips
On 2007 Feb 2, at 1:03 PM, Neil Mitchell indited:
An import list is not a value, you can't examine whats in the list, you can't enumerate it etc. As such, it doesn't really matter how many elements are in there, the important thing is what the elements are.
I don't know enough about it, but mightn't Template Haskell disagree on that point? Or any other source-level manipulators? (perhaps that shouldn't be a consideration?)
Well, Template Haskell is an extension and not part of the current Haskell 98 standard. And as far as I know there's no effort to make it part of Haskell Prime. So yeah, probably it shouldn't be a consideration.
You just highlighted the inconsistency: You refer to "import lists"... you appear to think of the import syntax _as a list_, and it is precisely that mental processing where the inconsistency hits/grates. If it is an "import" _list_ it can have trailing commas, but if it is some <other> _list_, it can't. I don't see the justification for making those two cases different.
The thing that I think Neil and Ganesh were trying to get at is that an import list can't appear in just any context (that's what's meant by it not being a first-class value), so Haskell programmers *do* usually think about them differently. Cheers, Kirsten -- Kirsten Chevalier* chevalier@alum.wellesley.edu *Often in error, never in doubt "Man, you're not so perfect / Man, you're not a pearl / You're nothing more, man, than a little piece of sand / That grew up inside of a girl" -- Jude