Existential types: want better syntactic support (autoboxing?)

Philippa Cowderoy flippa at flippac.org
Mon Jan 30 22:07:35 EST 2006

On Mon, 30 Jan 2006, John Meacham wrote:

> well, jhc would also need to pass a type parameter rather than a
> dictionary in so it would likely have a similar issue.

It's not an utterly insane idea to carry a type parameter with every value 
(except those for which the optimiser figures out it's not used) though, 
whereas you can't include all dictionaries with a value.

> although, that raises another good point about autoboxing, [Foo] and
> [Int] would necessarily be different types. so how would you convert
> [Int] to [Foo]? (map id)? 

Point, I'd been intending to mention that too. Autoboxing bugs me in a 
number of ways, most of which I imagine can be phrased as "inconsistency".

flippa at flippac.org

'In Ankh-Morpork even the shit have a street to itself...
 Truly this is a land of opportunity.' - Detritus, Men at Arms

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